If you're sticking to using web-based access for your mail, there's probably not anything you can do about it.
If you switch to using an email client, such as Outlook Express, you can also use Mailwasher which will prevent most spam from being downloaded to your PC:
http://www.mailwasher.net/
Many people use 'disposable' email addresses for things like online purchases and signing up to AB, so that they can easily ditch them if they start getting spammed. (The idea is to keep your 'prime' address secret from all but your best friends). It's also a good idea to choose an email address which won't be guessed at by a spammer's computer. (For example, a computer can send mail to sarajones, sarasmith, saraprice, sarapeters, etc, at hundreds of different domains. Those names are easily guessed at. However, if you have an address like
[email protected], it's unlikely to be guessed at).
If you want some disposable addresses, use Gmail or Gawab. Instructions for setting up a free Gawab account are in paragraph 3, et seq, of my post here:
http://www.theanswerbank.co.uk/Technology/Inte rnet/Question407429.html
Chris