Stuff we're building on:

• Python. Excellent book is dive into python. For those who learn by doing, learn python the hard way is unparalleled.
• Django. Their tutorial and documentation is absolutely world-class. We are trying to build things in the most Django-y way possible.

You'll want to learn how to use git, which can be a bit intimidating for newcomers. Tons of tutorials here, including git reference and the free pro git book.