There is no such thing as Spyware for the Mac. What you saw was a fake web site running a FAKE program telling you you need to buy their stuff, which is Windows by the way. You may have some other issue, DNS, Cache, etc., but you DO NOT have Spyware.
You could also try to empty out your out your cache under the Safari Tab. Computers tend to store so many short cuts there and slow you down after a while. Also if your running Parrals on your Mac like I am you could have a virus hanging out there. Mac Mall . com has a good virus program called Virus Barrier X5. Im using it and it finds everything