if you are trying to control 12v LED strips from the Arduino just follow the instructions here
http://fritzing.org/projects/arduino-controlled-rgb-led-light-strips/
These look awesome, and I'll definitely keep them in mind! Though, first, I'd like to take some time to make my own circuit to drive my LEDs as a learning experience.
if you want to make something your self just get 3 logic level mofsets one for each color and make sure you hook them up right or you will toast the Arduino
I'll research and look into getting some mosfets, as well as a ULN2803 for my needs, perhaps I'll get both and learn about them!
Thanks!