Normally I don't get involved in these types of recommendations but I for one can relate to your situation about the "novice" + computer building. As has been recommended I strongly suggest you have someone close to help you. If that is not possible check in from time to time here and you will probably get some good advise from some willing people to help you. Something that I struggled with was the PSU and the case. PSU is very critical in that it is the heart of your system. You don't want to skimp on that. So many things can domino from a weak PSU. The case is going to be the foundation to your computer, since this is your first case I would strongly suggest getting a larger tower for numerous reasons. First time build you will need all the room you can get to become acclamated to your project. Second, a larger, well venilated case allows the heat to dissappate more readily. I ended up with a coolermaster stacker. Love it. Next build is going to be a stacker also (well made and rugged). I opted for a PCP & Cooling PSU. Somewhat overkill but am satisfied. There are many other PSU's that can give you adaquate power, OCZ POWERSTREAM is a dandy. You may want to consider going to monarchcomputer and purchase a MB combo that way they install the chip and thus allowing you (since this is your first build) not having to do it the first time. In additon they give you some free games.
Could add more but feel like i am starting to ramble
good luck
jd