Also you may want to check out Ben Heckendorns xbox 360 laptop.
Step 1: Gathering the tools and materials
xbox 360 (Mine had the red rings)
LCD computer monitor (My dad got a broken one from work and I fixed it)
Now in case you don't have the money to buy a new xbox and monitor see if you can find an xbox with the red rings and a monitor that wont turn on. I fixed my monitor for about $5.00 and it works great (the problem was two bad capacitors).
Step 2: Taking apart your xbox
Here is a link on how to do that:
Step 3: Fixing my xbox
Reflow xbox 360 link: