Here is a partial list of some of the tools you should have. It is a partial list becuase a person can never have too many tools. :rotf:
Three good straight bit screw drivers. One small one medium and one large. When working on guns, the most common mistake is trying to use a screwdriver that is too small for the slot in the screw. This will always booger up the slot making it look like a beginner attacked it. If your stock of screw drivers do not fit the slot be prepared to buy another one that does fit.
Medium sized Vise-Grips. These are handy not only for grabbing things but they can serve to hold small parts while you work on them.
Flat Files. A 8 inch and a 10 inch flat "Mill" file and a 6 inch triangular file.
An electric hand drill plus an assortment of good drill bits.
A plastic or wooden mallet. Not too big.
A small hammer. Claw or Ball Peen will be fine.
A center punch made for steel.
A small vise. A 3 inch Pony (brand) that can be clamped onto a table is very handy.
A Propane torch plus fuel.
8 inch Adjustable wrench.
A 1/4 inch wide chisel. Buy the best you can get. Sears Craftsman or Ace have some that are good enough.
Sandpaper. For wood, IMO the red garnet kind is about the best (80, 120, 220 grit) For metal get the "wet/dry" silicone carbide paper (120, 220, 320, 400 grit).
Of course you can buy a electric drill press, electric belt sander and a electric bench grinder, thread taps and tap drills... but for basic work the tools I mentioned above will be a good start.