I would first figure out where the Cable/DSL/whatever line will be entering your house. (Most likely in the back somewhere). If you want to have an actual network closet, you could put it somewhere near this point. Otherwise what I did was just take the cable modem and my router and attach them to the floor josts (ceiling in the basement) right at that spot. Then I ran cabling from that central location to each room I wanted the network in. You only have to run one cable to each room because if you need multiple connections in a room you can just plop down a small hub to get you the extra connections.
If you want wireless in your house, it's always best to have the wireless router located in some sort of central location to get the best coverage.
Here's my setup in a nutshell.
4 port Router in ceiling of basement near wall where cable comes in.
1 cable going to each of 3 bedrooms and 1 going towards the center of the basement.
4 port Hub in the main bedroom used as the computer room. 3 computers plugged into this hub.
4 port wireless router in center of basement (in ceiling) to provide maximum coverage
1 cable from this router going to far wall of basement where the XBox is (opposite end of house from first router.
I have no problems at all with this setup. I can easily add more ports if I ever needed to. I can go wireless with my laptop when I want, etc.
The main thing is you have to have to pick where your main router is going to go and run all the cabling back to that point.
For wall plates and such, I got all my stuff from
http://www.lanshack.com because they had the best prices by far. All the items I got from there worked flawlessly as well. As for making cables you'll need cable (duh), plastic ends, and a crimper tool. Its very simple. Might see if you know anyone that has the tool you can just borrow.