Well for a start don't post your email address on websites etc. If you have to, put it as, for example "fred bloggs at bloggsnet dot co dot uk", i.e. typed in full rather than putting all the symbols in. This is cause these people that send you all this crap send little webcrawlers out on to the internet looking for email addresses on web pages to send junk mail too. Once they've got hold of it, you're done for. But you can reduce the amount you get in future if you change what you're doing now.