Reddit mentions of General Tools 450-6 Flat Leg Divider, 6-Inches

The tandy beginner set is geared towards tooling, which certainly does require veg tan. Depending on whether or not that's the aesthetic you are going for, you may not need the swivel knife and stamps (or you may want many more stamps). But at it's core, you need:

• Something to measure with (metal ruler)
  
  
• Something very sharp to cut with (Utility knife / Rotary Cutter / Round/Head knife)
  
  
• Something to attach pieces together (Contact Cement + either Rivets or Waxed Thread/Harness Needles)
  
  And a slight step above that is something to finish edges (acrylic edge paint, water/gum tragacanth/wax etc.)
  
  I personally do not do a lot of tooling, and also usually use stitching (vs rivets), so if I were going to recommend some starting tools I would say
  
  
• Cork-backed Metal Ruler
  
• Seiwa Pricking Irons
  
  
• Ritza Tiger Thread
  
  
• John James Harness Needles
  
  
• Olfa Rotary Cutter
  
  
• Wing Divider (used to mark stitch lines)
  
  
• Contact Cement
  
• Some variety of beeswax or paraffin, I like this stuff
  
  
• Some scrap pieces of canvas and soft cotton for burnishing an edge (old jeans and t-shirts work great)
  
• Some Misc. items you probably already have like sandpaper and super glue from time to time.
  
  Edit: I didn't include an awl because the Seiwa irons are designed to punch through, but a good diamond awl from Bob Douglas/Barry King or similar would probably be my first upgrade to this set of tools.

Thanks for the interest. I used 2-3oz economy leather from Tandy Leather. Here's the list of tools I used:

• Swivel Knife
  
• Nylon Mallet - I have the Al Strohman version, got on sale.
  
• Beveler Stamp - Perimeter edge
  
• Background Stamp
  
• Wing Divider - to mark stitching line
  
• Hole Punch
  
  Finished with:
  
• Saddle Tan Antique Gel
  
• Neatsfoot oil to soften
  
• Tan-Kote to seal/protect the leather
  
  Hope this helps