I think the hard part is finding your questions (you want to ask your mentor). Once you have them, finding answers is pretty easy. The best source may be books,

I think the hard part is finding your questions (you want to ask your mentor). Once you have them, finding answers is pretty easy. The best source may be books, because authors have thought hard about the answers. 2nd blog posts, because those people too had something to say on the topic. If you ask a random person anything you will likely get a random answer. 3rd find an expert on the topic of your question. Finding a mentor first and your questions only then seems backwards.