Water damage isn't a problem you want in your home. Ceiling leaks can cause something as mild as staining to something as problematic as remodeling the whole area around the leak. But don't get discouraged. Take the time to look at it yourself and save yourself the headache of having a contractor complete the repair.
Troubleshoot the problem. Start by eliminating all of the things that it can't be. Ask yourself if it could be the roof, a kitchen or a bathroom. If it's a roof problem, look at eHow's article on roof leaks.
Check the room above the ceiling leak. If there is a kitchen or bathroom there, make sure no water is coming out of the toilet, sink, bathtub or shower and onto the floor. Check sink drain pipes to make sure they aren't the source of the problem. If they are, see the related articles on eHow.
Look at the seals around bathtubs and the tile grout in the shower. Plug any gaps or holes with caulk or regrout the area in the shower. Look at the seal around the shower door and ask yourself if there's usually water on the floor after your shower. If you've eliminated these as problems and still have a leak, move on to Step 4.
Call a few plumbers if it turns out to be none of these issues. Get several quotes for repairs and explanations for what they want to do. The plumber you select might rip out part of your ceiling to find the source of the leak.
Let the ceiling area dry out for at least one week after the leak has been fixed. If it hasn't been leaking for too long, letting it dry might take care of the ceiling.
Look at the beams, the insulation and the drywall from the top side of the ceiling, if you have access, to see if the problem has cleared up on its own.
Read eHow's article for how to repair a drywall ceiling if it shows signs of permanent damage.