Half-Life Zone is young, keep that in mind.
However, even for a brand new site, there’s still quite some stuff here to check out.
You’ve got a large listing of useful programs, not just for mapping, but for modelling, programming and creating sprites as well. You’ve also got some resource listings, though they kinda say bad s**t bout HIT or something.
Tutorials seem to be in progress, for now.
There’s even forums, too!
Overall, check out HLZ. For an early site, it seems to be doing well, and let’s hope it goes far!