I learned about NPL from Famulus via his Tough Cryptics publication. (I was hanging out with Daz at the time, but he never mentioned NPL.)
Source: Postcard to Meki from Crax.
First Issue: Apr 1993
No data.
[ Codex's ] only combinom appearance so far is Codax (with Crax)–this *may* have the distinction of being the first combinom for base-finder and artist in a picture flat.