I'm some kind of modern Faustus. While he sold his soul to the devil, I've sold mine to Google. Their gmail is excellent. While I do have an email account with my ISP I never use it, but it's there as a back-up if needed.
Although they're not regular email providers, there are a number of anonymous email outlets that can be used if we don't want to give our address to somebody but need to have them contact us.
I use http://www.spamgourmet.com.
I registered once but am able to set an unlimited number of temporary addresses, as well as set the amount of time they will be maintained. So, by setting a three day limit, any spam sent after that time just disappears down the gurgler.