ATSTK525 Starter Kit

I got an email from Digi-Key about a special they are running:

Through January 31, 2007, Atmel is offering Digi-Key customers an exclusive discount on the ATSTK525 Starter Kit. This kit, which typically retails for $197.48, is available for $148.00. (Limit one/customer)

I have been thinking about doing a usb host project. So my question is what are the tools like. Specifically how do build, I download to the flash, and test my code? It does not say if the processor can be programmed in C?

The ad says: "It supports JTAGICE mkII and AVRISP mkII via AVR Studio." I don't know what any of those three things are, but do I need additional jtag hardware? What does it cost?

I went on the Atmel website, and it did not clarify anything for me. It seems that many useful items are available for free download at the cost of signing up (and I presume reams of spam).

What I would like:

1) A cheap eval kit like this. 2) GNU toolchain including GDB for debugging. Windows and/or Linux based. 3) Decent chip and dev board docs and schematics.

Does anyone here have any words of wisdom on this board and development environment?

Thanks, Steve