Depending on the language, usually... Google (of course). Then apidock.com (for ruby / rails) pretty much the best doc site for either in my opinion.

For Rails I have found that just browsing the source/comments on github is the best source for figuring out really tricky issues. I stay logged in to IRC but most of the time never feel like bothering anyone. I kind of enjoy figuring things out for myself, even if it's a trivial problem I still get satisfaction from solving things on my own.