Heck, bwoy were did you here that? And what the fuck is Spyware? What kan i get to prevent shi_te.
Spyware or ad-ware is a 'feature' in an application which 'calls home' as E.T. would say. The most common features of spyware are that it tries to send you IP address, what you do with the software, statistics, et cetera to the producers of the application.
Spyware software is very often freeware. There are mostly non-spyware applications as well which have the same functionality as the software which includes the spyware, but those very often cost (more) money.
Ad-Aware is software which works via a database which contains most (not all) known spyware and tries to kill that part of the application. In some cases that leaves the application in a not working state.
Try to look for software which does not contain such spyware. A personal firewall is handy to block unwanted outgoing (not incoming) traffic incase you still want to use software which contains spyware. Installing Ad-Aware is a good thing to do then too.