I basically got into this project after purchasing an x-arcade controller from X-Arcade. The controller came with 6 games, Gauntlet, Joust, Defender, Robotron 2084, and Rampage. The controller played the games great, but it still did not feel like a real arcade cabinet. I started searching the web for people who built a cabinet for their x-arcade controller and found a whole world of people that went well beyond that.
My project started when I purchased the book Project Arcade by John St. Clair. After just a few pages, I was addicted and felt "I could do this." I never built anything major in my life, so this was going to be my first major construction project. The book did a great job of preparing me for what to expect. I highly recommend it.
The book comes with a couple of sets of cabinet plans. I followed the plans based on LuSiD's Arcade Flashback.
Another good source of information was the BYOAC (Build Your Own Arcade Controls) website. There is a great source of knowledge there for helping a person build their first cabinet.