if you like video instruction here are some good youtube channels on using AVR chips with Atmels Studio 6
which is what i have personally been doing my self just trying to broaden knowledge into AVR microcontrollers in general as oppose to strictly Arduino Patrick Hood
playlist INtro to Avr MicroControllersHuman HardDrive
Human HardDrive - INtro to Avr - C - programming
Ive learned a bit from both these guys , make sure to brush up on your bit shifting and operations or just write a good macro to keep it simple
and get the chips datasheet , set is as your desktop background hahhaa youll learn the pinout in no time.
Also get a programmer , i use tinyISP but its requires some work to get it all working with Atmel studio.
If you get a supported programmer like MkII (MK2) then it is supported off the bat.
Enjoy. its rather fun and the Atmel Studio is based on VIsual Studio which is pretty neat. in my opinion of course
if you want example code search perhaps AVR Freaks