may i suggest www.endjunk.com
you can keep your email address but when you sign up for something you can put
for the email address, this is useful for two reasons
one is once you get spam from that account, just go to endjunk.com and block it from there, they shut down the fake email account and you wont get any messages sent to it, it also will show you who is selling your email address and you can take the appropriate actions...
for example say you sign up for a service at www.google.com
so you use the email address
then you start getting tons of spam, look who it was sent to, if it was sent to that email address, you know who did it.