In Norton Personal Firewall, block his IP address permanently.
You can do this under the internet zone control options. Add his IP to the restricted list. If he's good, he'll come at you with a new IP...Just keep restricting them. The good thing is, your firewall software is working fine!
If you want to have some fun, you can trace his IP address here and get an idea of where the attack is coming from.
http://security.symantec.com/ssc/vr_main.asp?langid=ie&venid=symnis&plfid=23&pkj=OFFJCVGZBZTVOGXFSTZ