There are some thick PBT options in this thread:
http://geekhack.org/index.php?topic=59780.0Not sure what colours you like most, there are quite a few options out there, some cheaper than others.
Bunnylake will be running a new Group Buy soon for a GMK version of the HyperFuse set. GMK makes thick ABS doubleshot keycaps in Cherry profile. Absolutely top quality caps.
I'd take a browse through the Interest Checks and Group Buys section to see if any of those sets strikes your fancy.
If you want an interesting old skool cold war terminal keyboard look, there's the Nuclear Data Green GB in SA profile running right now:
http://geekhack.org/index.php?topic=61198.0Another SA profile keyset that will have a Group Buy running soon is the Pulse set, but this one will have contoured profile (different angle for each row):
http://geekhack.org/index.php?topic=61822.0The SA profile caps in these sets are thick doubleshot ABS. If you like that profile, it's a good time for it. Matt3o will be running either Midnight or Retro Group Buy in SA profile after Nuclear Data Green completes. Probably with the option for all Row 3 or contoured.
I believe IvanIvanovich will be running another GB once the current 2 complete (GMK Dolch and Pitch Black - black on black PBT). There's a chance it'll be for some thick POM caps, or perhaps another PBT set.
Welcome to the hobby! Mind your wallet, though, it's addictive and can get expensive!