@pete_pumpkin
On your Workbench screen, select the "About" item in the "Workbench" menu. Here you'll see revision numbers for both your Kickstart (the ROM chip), as well as for Workbench itself. A 40.68* revision means that you have the 3.1 ROM chip, a lower number being 3.0.
Also worth a look for places to buy software is
Amiga Innovations. That's a West Australian-based mail order business. I've ordered there before and found the service pretty good.
*I'm sure someone will let me know if I'm wrong, I think this is the revision which a 3.1 A1200 will report. I myself have an A4000, so can't check for sure. As I recall the 3.1 chips themselves are different (eg support for PCMCIA slot on the A1200), but report the same revision.
