Honestly, in your budget, I think your best bet is going to be focusing on building your library. You can get the same benefit from conferences by snagging the webcasts and papers online. Colleges and Universities (other than mine, and our backend courses probably won't be ready for another 6 months or so) don't really teach Python, and the Java they teach is academic. Plus, you are looking at $500-$1000 a credit for anything decent you might find.
Certs are nice for networking and security, but for application development, experience counts for way more.
So, as much as it kind of sucks, loading up on the reading material is where I would spend my budget.