Sometimes, Mac software is distributed as an installer. Potentially that leaves a bunch of files strewn all over your Mac its filesystem. One tip is to run the following command before installation:
$ find -x . / > before.txt
Then install the software, and run it once. Quit, then run the following two commands:
$ find -x . / > after.txt $ diff before.txt after.txt > filelist.txt
Now open the filelist.txt and you'll see a rough list of all installed files. Both as a result of the installation, but also takes into account whatever the software wrote in your ~/Library folder.