The bus station of Mossel Bay is actually 7 kilometer removed from the city centre, so unless you're coming on the BazBus, you'll have to arrange for a taxi to get you to the centre.
The bus station is at the Shell petrol stop.
For Mossel Bay, you'd better have a car!
Although it's possible to get to Mossel Bay by bus, train, and air (George Airport isn't very far away), you'd better plan to rent a car once you're there. We saw no evidence of any kind of city buses or trams. There may be a few taxis around, but they weren't exactly visible. For good or ill, a car really IS a necessity here.
There is an Avis in Mossel Bay, so you can rent a car there or drop it off and see the surroundings. Avis is at the petrol station across the street from the bus station.
- Road Trip