Do you need to enter your email address on a web to receive an inportant email, but fear your address will be spammed?

Just head over to www.pookmail.com, a site which provides disposable email address for this very purpose. Just use any arbitrary name, for instance fakeaddres@pookmail.com, on the web site in question. Go to pookmail.com and sign in with the same name, there's no need for a password.You'll see the email you requested, and you can save it, delete it or just abandon it. It will automatically be deleted after 24 hours, and your own email account will be safe from spammers.

Also, another useful one is spam gourmet, if you are more sensitive about your data.

http://www.spamgourmet.com/disposableemail.pl

After you sign up for an account, you can use emails like this:
someword.x.user@spamgourmet.com
just use a unique thing for "someword", the x is the number of emails you want to recieve, max, for that email address, and user is your username. Also useful. If you were confused by my description, don't worry, the site explains it well.