Just off the top of my head:
Brownell's Magna-Tip screwdrivers.
The Master kit is the best and will take care of about 98% of the screws.
Extra size bits are cheap.
Best of all, if you break a bit, Brownell's will replace it if you email them.
A good set of standard pin punches.
A set of "starter" punches.
The starter punches are simply punches with a short length that makes driving out tight pins easier. The shorter punches are stiffer, and don't bend or flex.
A set of roll pin punches.
If needed, a set of dome-head punches for driving out round head pins.
An Opti-visor magnifier in your choice of focal length.
A good adjustable bench light.
A bench pad.
I used rubber "Poundo" pads sold by Tandy that are used for punching holes in leather.
These are black and 1/4" thick.
Watchmaker's tweezers.
Small, high quality watchmaker's smooth jaw pliers.
Small hammers in steel, brass, and plastic.
Parts containers.
These can be any small plastic container, like Tuperware.
Jerry Kuhnhausen shop manuals that may be available for the guns you intend to work on.
Specific tools for the guns you intend to work on. IE S&W revolver rebound spring tool, S&W ejector rod vise, Colt revolver bushing tool, Remington 700 bolt tool, etc.
A GOOD small adjustable vise. One that has the most amount of different positions so you can position a part properly to work on it.
The small "Versa-Vises" are OK for very light work, but you'll need a good watchmakers vise for anything that really needs to be held.
As big a shop vise as you can afford for holding larger items.
Brass and synthetic material to make vise jaw pads.
As many different files as you can afford. Buy gunsmith and machinist types instead of hardware store types.
A set of good needle files.
File handles for all files.
Several ceramic stones.
Square, and triangular are best, and ceramic since they don't wear and change shape like synthetic or Arkansas.
I hesitate to say it, but a Dremel or Flex-shaft, and a selection of rubber-bonded abrasive tips, and sanding drums.
Small drill bits.
A drill press.
One of the cheap Sears table top models will do.