Ya should check around your area for clubs. It doesn't mention in your profile where your from. Toss it out there. Who knows, there may be some of the folks here right around the corner.
You mentioned the window issue but what about a porch? back yard? I live in an apartment on a busy street and although I have to fight the crackheads from stealing my trees I've been able to make it work. The reason I ask is because your living situation can limit you greatly. Or just narrow down the species you'll be able to work with.
I think that little fatty you've got looks great and has lots of potential. Great tree to start with and like you said "keeping it alive" is the best place to start.
Welcome to the addiction we call Bonsai.
