Geoff, using "machinist quality" tools are a real plus in the woodshop. Ditto the previous recommendations about Starret, Brown and Sharp, Mitutoya, etc.
Other "good quality" machinist brands are Central (US made - not to be confused with the "Central Freight" brand of tools), General, etc.
In addition to Enco, J&L Industrial Supply sells high quality machinists tools at good prices. I've found that J&L's quality is usually a level above Enco's.
In addition to a high quality square, the measureing tool that I use the most in the woodshop is a 24" flat steel rule, that has inch measurements on one side (1/8" and 1/32" scales), and metric on the other (mm and cm). I really like this rule as it's quick, easy, and with today's multiple references to metric or english, it's an "all in one" solution. It's made from flat ground stainless steel, so it doubles as a straight edge (as long as I'm careful how I store it).
Dial calipers are great - for woodworking you don't need Starrett (although they are nice).
A set of machinist squares (various sizes) are also handy.
Good luck with your acquisitions!
Scott