I am a beginner player that has just finished Guitar Fundamentals I and I'm working on II. I've been practicing pretty regularly (as often as my hectic schedule allows) for the past 5 months. When do I need to change my strings? I have a feeling I may need to do so now but I'm not sure what I'm looking for in effects that would let me know that. I have an electric guitar (it's a Frankenstien that a friend put together for me using several different guitars for parts). And what is the best brand/kind of strings out there that I should be looking at that won't break the bank?

Thanks!