I know how to map, it's just I SUCK at mapping. I make maps but never get any better. I need some HL1 map decompiler to find out how all this stuff is done.
Find some mapper friends.
Source SDK Makes things a little easier. But goldsrc is where the funs at.
I'd probably take a look at doing a map for CoF. First of all, find the model of the giant head, and the sound. Second, make a huge maze with every bad way with the giant head and sound. Success.