$15 gets you an account to report unlimited spam to
www.spamcop.net.
They do he research on their servers and send out the abuse reports for you. They process tons of spam per hour.
I've also been running McAfffee's Spamkiller Pro, you can setup custom filters and greatly reduce the same that actualy makes it to your PC. It'll check your POP mail and weed out stuff every XXmns if you want.
There are other programs that do this as well, most you have to pay for, some even work with AOL.
I have been filtering all my mail through spamcop.net, but unfortunadely i can't get my hotmail to forward to that account, than they re-direct it back to you. You can still access the messages it catches, as you need to manually send the reports in.