Uninstalling an application on a Mac is the easiest thing ever: go into your Applications folder, select the one you want to remove, and drag it into your trash.
What most users tend to overlook, and therefore never get rid of are the preferences files associated with these applications. With time, these files can clutter up your drive.
PrefCleaner is a simple little freeware tool to get rid of them. Once it's open, just drag a program's icon onto it, and PrefCleaner will get rid of all of it's preferences file.
Unfortunately, PrefCleaner only works one app at a time, so if there are many applications you want to get rid of, you'll be there for a while.
The other nag we have with PrefCleaner is that it closes automatically after it has done its job so you will need to open it up again every time for each new program.
PrefCleaner is useful for removing preferences files for only a few program. If you need to perform the same task on a larger scale, try out