For the Atmel AVR series, I don't believe it's possible to program it in VB. There isn't a VB complier, from what I know, so you have to use either C or Assembly (recommended, since it's easier to switch to assembly from vb). The best thing to do, is to download AVR Studio (
here). It'll let you write the code, and emulate it, so you'll know if it'll work or not. From there, you should be able to upload the code to your device, but how you plan to do this depends on if you bought a programmer or not.
Personally, I've just started with the Atmel AVR ATMega32, and I've found it to be more then enough for my needs. I'd recommend any of the Mega's, but if your going to be using a breadboard, buy a DIP version of the chip.