I am an IT Pro.
Here are some good tips:
Hardware firewall - they are getting cheaper but you get what you pay for remember that. I prefer some of the more commercial models in the $300 range to stop hackers. (Watchguard, Sonic Wall, Net Screen, Cisco{expensive unless you go on eBay})
Spam blocking - If you are using MS Outlook you can get "I Hate Spam" and I have found it blocks 99% of the spam I used to get. My customers all love it.
Anti-Virus software - There is nothing like Symantec Anti-Virus Corporate 8.X (Symantec is the corporate version of Norton, Norton lets through things that the Symantec AV Corp. does not!!)
Lastly surf smart! Learn about surfing security to block hackers that make site specifically to attack novice surfers.
Enjoy all !!