Actually, if we follow REAL geography San Fierro would be Northwest, Las Venturas to the east, and Los Santos to the Southwest.
I was going primarily based on what the lastes PS2 UK magazine showed, although they admit thier glimpse was brief and could be wrong.
Most sources do agree that Los Santos is in the lower right of the screen, and of course that section is accurate on the map I made.
As for Angel Pine, I didn't know how to rectify that problem. I know the first mission takes you there, so it would seem it is close to Los Santos, and yet Red County, the closest countryside to Los Santos doesn't contain Mt. Chilliad or Angel Pine.
I'd be more than happy to make a new version if you guys want to help figure out locations.