When i start I normally go, Fishing hut (sometimes 2 if its close), 2 fields (random crop, 2 differnt if available), wood chopper, then housing.
I would advise building homes as your very first task, with the only exception being some sort of food production if playing on normal/hard (you start with a limited supply of food, and run out fairly quickly if you don't start gathering right away). I also wouldn't recommend building any crops for the first couple of years. They provide less food per worker than any other type of food production (but they provide more food per amount of space used, which is why you will want them eventually).
I then build my forestry Hut, and herb (beside each other) and set forest to plant only.
Herbs grow better in long standing forests (i.e. ones that aren't being cut and re-planted constantly), so its counter-productive to place your herb gatherer with a forestry hut. Even if you only ever set it to plant trees and never cut, there is really no need for the forestry hut at all. I've had towns of several hundred citizens supported by a single herb gatherer who is just placed off on his own within a naturally growing/aging forest. You can place hunters and gatherers with the herb gatherer with no ill effects though.
Next spring i will plant a orchard (earlier the better I "think"? if i can manage it first spring I do, but its often hard unless fishing is very close).
Orchards are pretty unnecessary. The amount of wood they provide is completely negligible, and they take several years to begin producing food at all. In the first few years, you have much higher priorities. They seem to produce slightly less food than a crop field on average, but also need less workers, so efficiency is probably roughly the same. I think the only thing they give you that you can't get otherwise is nuts (fruits are produced by gatherers), and I'm not even sure that nuts count as one of the food groups (this is related to health). Certainly they can add some extra flavor to your town, but are hardly worth worrying about in the early game.
After that i add gather (by herb), Hunter (also by herb, or next closest forest area if large enough). School, and Blacksmith.
I would recommend getting a hunter up quickly (right after houses, and right along with your first set of food production buildings), and a second hunter not far behind. Unless you started with sheep or cattle (which is not possible on normal/hard difficulty), they are your only method of producing leather for clothing, and one hunter barely produces enough leather for your starting population.
So, Quarry, stone does seem finite, build one early or late? Mines, see no reason early in game. market, early or late?
There is a finite amount of stone on the map, but theres usually enough of it that you can survive a good 5-10 years without a quarry. Steel tools require iron (also a finite amount found on the map) and coal (cant be found on the map), and are more effective than iron tools. It isn't imperative that you get them immediately, but I would start mining as soon as you have the population to handle it, probably around year 5-8.
Smith- my people dont seem to quit working even if there are no tools, do they work slower (chopping a tree down with your hand has to be hard work).
Yes they do work slower. You start with enough tools to last several seasons, but getting a smith operational should be one of your top priorities, right after homes, food production, and firewood production. Iron tools are good enough for the first few years, but you should eventually work towards getting steel tools.
Schools, I assumed they only took kids- non labours, but i see people closing them and having instant labour. At waht age do they start to work? it appears around 10-11 to me.
I don't know the exact age numbers, but yes schools to extend the amount of a time before a new born child enters the work force. On the flip side, if you let them graduate from school, they will be much more productive workers for the rest of their lives. Its definitely a worthwhile trade off, but not one you can afford to make in the early game. Children and students use up resources (food, clothing, firewood, etc) but don't produce anything. Having your ratio of adults/students/children too far in the wrong direction WILL destroy your town. I usually wait until I have all of the basic infrastructure set up (housing, food, fuel, logs, tools, clothing) and am bringing in a surplus of food before I set up a school. Once you do, make sure to closely monitor your ratio of adults to students/children, and closely monitor your food supplies from season to season. I usually aim to have at least 60-70% of my population being adults.
Housing- I assumed i needed to make new housing to increase my population (nobody wants to ... um.. "join" with 5 people in the house.. but i get houses with 2 people in each (male-female) is this how you GROW population?
Population growth works like this. Each house will hold one 'family'. When a family moves in to a home, if they are of child bearing age, they will start to produce children. The max number of children a family creates seems to be 2, maybe 3 (not all at once of course). Barring job changes that necessitate they move to another house, that family will occupy that house for the rest of their lives. No other family can move in to that house while it is occupied. So if you build 10 houses, eventually you will get families living in each one, and you'll get a number of children. But if you never build any more houses, all of the children will simply continue to live with their parents, and be unable to produce children of their own. Eventually everyone will die of old age and your town will die with them.
Assuming you have a surplus of houses, new families (consisting of a male and female generally) will move into them when they become of child bearing age, and start producing children of their own. This creates an interesting dynamic that you have to continually manage throughout the game. You need to keep producing houses in order to prevent your citizenry from growing too old and eventually dying off, but not so many houses that you can't support the child/student population (which of course, will also kill your town).
To make it more challenging, all of these decisions have to sort of be made blind. Building houses doesn't immediately cause a surge in child births, there is a delayed effect, and often it isn't fully felt until you've been overpopulated with children for a year or two. Similarly, it isn't immediately obvious when you have waited too long to build new houses and your population is primarily too old. People live for quite a long time after they stop producing children, so you could be humming merrily along for several years without even realizing there is a problem until you start losing large numbers of people to old age. Suddenly you realize you need to start producing more children, only to realize that 80% of your population is too old, so while you put up a few new houses to start making children, most of your population is dying of old age, which is causing shortages in your production industries, which in turn is being exacerbated by your ratio of adults to children suddenly being skewed heavily in the wrong direction. This situation (which I've experienced a few times) will likely spiral out of control, and kill the vast majority, if not all, of your citizens. God forbid you have to deal with a disaster at any point while trying to recover from this.
Are somecrops better then others?
Not that I am aware of. There are specific 'food groups' though, and achieving maximum health is dependent on your people regularly eating all four of them. I believe they are grains, vegetables, fruit, and meat. Grains (wheat, and I think there is one other type of grain) can
only be produced on farms (obviously you can purchase them from traders as well, but this is an unreliable source to count on, especially as you grow larger). Meat comes from hunters, herders, and fishers (venison, beef, chicken, lamb, fish). Fruit comes from gatherers and orchards. Vegetables come from crops and gatherers.
Vegetables are the easiest to maintain a steady supply of. Most of what your gatherers supply is vegetables, and most of the crop types are vegetables (so its relatively easy to get one of the vegetable seeds).
Meat is also relatively easy unless you have very poor river/lake access (which is pretty rare on most maps). If fishing isn't viable, your only supply of meat for quite some time will be hunters, and while they are vital for getting leather, they are a very poor source of food (comparatively). Eventually you will be able to supplement your meat supply with chickens/sheep/cattle, but animals are fairly rare to find on a trader and very expensive, and it takes several years for your animal population to max out (you don't get any meat until the population maxes out and you start slaughtering them to keep the population in check).
Grains are obviously very difficult to maintain a supply of until you get a grain seed. Once you have that, just make sure to plant a lot of it and you never have to worry about it. Getting a grain seed should be one of your top trading priorities in the early game.
Fruits are a bit of a mixed bag. Your gatherers collect berries, which counts as a fruit, but its only 25% of their total haul (roughly). Not enough to keep your population constantly satisfied with their fruit intake. The only other source of fruit is orchards (unless there is a crop like strawberries, but I haven't seen a fruit crop to this point). Orchards also require you to have a seed (its likely you will start with one on easy mode, somewhat likely you start with one on normal, and not possible to start with one on hard mode), so after obtaining a grain seed your next goal should be a fruit seed. Orchards of course require several years to start producing food, and produce slightly less food than a crop, so you will need quite a bit of space to maintain your fruit supply. Orchards can also be planted to grow various types of nuts, and while I'm not positive on this, I believe nuts count as vegetables.