Hello 3 eyez,
Just want to say I am also 15 and a first timer and have been researching the site for quite some time now and have also bought the book "Project Arcade". I have already built most of my Pc for the cab and have boughten a 19 inch tv to put in it. I have some advice for you.
1. If you don't want to spend much money on your cab and can aquire a set of powertools, use particle board, its one of the cheapest woods, and primed a few times and painted a few times, you cant even tell its particle board.
2. You are not supposed to request roms on this site, <nuff said --- saint>
3. When posting on this site, ask specific questions at a time instead of a bunch in one post, I found that this will give you more detailed replies and answers.
4. Alot of times when looking at other peoples example pages they will have links with the measurements for their cabinets. just go to the examples page at this site.
5. Use ebay, You can find great deals on parts,
Hope I could help for now, The3eyedblindman