I get heaps of those share price email things every day. Most of the ones I get are directed to email accounts used to register domain names, which spammers can retrieve from checking the domain register.

Trick to avoid SPAM:

Always have 3 email accounts -

1. Private account which only friends/family have. This can normally be your ISP account. DONT give this to friends/family who send those chain mail letters around (you know the ones, pass this on to 10 people in 10 minutes and the love of your life will phone you kinda rubbish). If you notice, 6000 other peoples email addresses are listed in the body of the message from where it's been sent around, and yours will be as it gets sent on, so it only takes one person with a virus on their PC unwittingly give away all those addresses to a spammer.

2. A trusted web account which you use for signing up to trusted accounts such as internet banking, or the like. It's rare to receive junk mail to these addresses, but you can receive a lot of marketing junk so it keeps it seperate from your private emails.

3. SPAM account, for signing up to untrusted websites, or displaying on the internet. A random Hotmail account is good for this kind of thing, as it's good with filtering out junk.

Although this doesn't really solve the SPAM issue, it at least means your personal inbox isn't invaded by unwanted scams all the time.