I agree with pString about the Dan Erlwine's book -- it is a great read. With the knowledge pulled from it and some good old elbow grease, I have brought a Washburn OE30 from almost unplayable to downright groovy.
As for my strings - I prefer a heavy gauge .11 (Ernie Ball Power Slinky's) for the Washburn due to its short scale length. However for my Harmony Strat copy I like .10s (Elixir brand)
Coding my way to the next BSOD!