You've got 2 options.
1) Trace & Report each & every spam message to the originating ISP. Somewhat successful though very very time consuming.2) Never post any working email address to any internet forum or NG.
At this point you're email address is being sold 100x over to the worlds spammers. Sorry to be the one to tell you, get ready for the onslaught of breast pills, penis pills, mortgage offers, etc, etc etc.