There are some apps that will have an uninstall app in the folder with the installer, like Safari 3.0 beta does. Most of the time just dragging the app to the trash like others have stated. There are some other files and folders that are located through out the disk, for the part these are really small pref files that only take up around 7-20k, others like LimeWire or the like will place a download folder in your documents folder. If you type in an apps name into spotlight it will highlight all of the folders and files associated with that app.
But for the most part just getting rid of the app itself is more then good.
Thats all there is to it n00b😱
enjoy your mac😀