Anywhere actually. I often find nice snakes even in built-up areas, so as long as you put in the effort you should be able to get something, but it is getting late in the season. Just make sure you get the identification right before handling anything, as we have quite a few venomous ones around as well, and many of them will definitely spoil your day, and some may spoil quite a few days...
The most common species for the area would be:
Short-snouted grass snakes (
Psammophis brevirostris)
Rinkhaks (
Hemachatus haemachatus)
Night adders (
Causus rhombeatus)
Puff adders (
Bitis arietans)
Brown House snakes (
Boaedon capensis)
Rhombic Egg-eaters (
Dasypeltis scabra)
Etc.
I don't post locality information anymore as many of my favourite haunts got raided by people who catch and keep snakes. So PLEASE release after you are done with the photographs!