Ya, we made the mistake of thinking Alamo was right in the terminal. It is not. We got on a shuttle bus, it took us to Alamo about 7 minutes away. We got our car. We phoned and asked if we could return it to the Alamo on Katella and take a shuttle to LAX, and we were told no, there was no shuttle. (we didn't want to have to drive in LA again, we had already got lost getting from Aviation Blvd to our hotel)
So we returned it back to the place on Aviation Blvd, and got on the shuttle back to LAX.
It says on the LAX website that there is 10 rental places right in LAX, but they are not. You will have to be shuttled out to all of them I am pretty sure!