When picking a transistor, I usually start with my supplier's catalogue and search and refine according to the specs I am most interested in. However, I seem to often come out with odd choices. For example I recently needed an NPN for basic switching of a 200mA current using an MCU, and ended up picking a BC337. It seems to work, however it also seems to be categorised as an 'audio amplifier' rather than a 'general purpose' or 'switching' transistor and so I can't help think I could have made a better choice (or maybe it doesn't matter). Likewise, I have a big bag of BC548's that I use a lot, because I happened to have one in my first 'beginners' set, and as it usually worked I just stuck to that regardless of if it was the best choice.
I think I would find useful a simple chart with the most common types, and their characteristics, that I could print off and have to hand to simply look up a suitable type. Google searching has found a few charts from the 60s, a few books (at ridiculous prices, nearly as out of date) but not a simple 'picker' or 'comparison chart' that I can find.
Can anybody recommend one? Or is there a simpler method for picking? Or does it really matter what the 'type' is if I'm just using it for switching (as I always am at the moment, as I'm only doing digital circuits so far)?
Maybe a better simpler question is...how do YOU go about picking a transistor for a switching job?