I know the models for Quake# and Half-Life can be pulled up in Milkshape and exported in whatever formats it supports, but I don't know about the levels... I'd do like the others said, and check out the game sites... I know there is a big Half-Life Map Developers section on PlanetHalfLife, go to www.contaminated.com to check it out. Poke around the mapping sites, and you'll find what you need. I just play 'em, I don't build stuff for 'em...