Where can you get info on how to change rear brakes on 1999 Camry CE?

You can get in any local auto part store.

Put your car on the parking breaks, lift it up, remove rear wheels. I recommend do disassemble both sides in the same time in case if you forgot how to it back one of the sides will serve like example.

Remove a drum, you can use a hammer or two screws if certain size. To figure out which size you need you can use two hole which are going through a drum. Them just remove the drum using screws or a hummer. After you did that you will see breaking pads. Remove them and put everything back with already new breaking pads. The same other side.