Step 15: Download Development Enviornment
WinAVR is a suite of tools to program Atmel's micro-controllers within Microsoft windows OSs. This is what I'll use for this instructable to code in C.
AVR Studio 4 : If you are the type of person that enjoys the speed and efficiency provided by banging your head on a rock.... erm... I mean .... programming in assembly. Well then you could do a lot worse the by going with Atmel's own tools. Actually AVR Studio 4 is pretty powerful and the environment I first started this project with. I'll give the code that remains from then as well.
Linux: For the power hungry nerd in all of us.
CrossPack : "Hi I'm a Mac"
Also if you'd like you can hop on the beta for testing out AVR Studio 5 AVR Studio in C using BOTH the GCC and IAR compilers if I'm not mistaken. Not used it yet but this is looking pretty promising as well. Way to go Atmel!