Hey Glen!

Too bad I'm a bit too far north to meet up with you.

The MTA bus system strangely doesn't allow free transfers. Depending on the bus lines you're connecting from and to, you can purchase a transfer (and I'm not completely clear on which buses you can do that with), but if not, then you have to buy a separate one-way ticket when you get on the next bus.

The rules are different for the different transit systems in the area, though, so on some, you may be allowed to transfer at no charge. I think going to the Getty Center, you'll be using the MTA system and not anything else (like the Santa Monica system, etc.).

The trip planner that FlyinHawaiian linked to will give you the total cost, including available transfers, for your trip. Google Transit will also give directions over most of the L.A.-area (and is usually easier to use), but fare information isn't displayed there.