"I have signed up to OnePoll Cashback and since then have been received weekly emails about new deals, etc. There is no unsubscribe link on the email, and when I have emailed them to ask how to unsubscribe, these emails have been ignored. The email address from which I received these emails is alerts@onepollcashback.com. How can I get them to stop sending these emails? I don't even think there's an option to de-register from the site."

One Poll Cash Back is registered in the UK and so its marketing practices should comply with the Privacy and Electronic Communications Regulations 2003. These quite clearly state that they have to give you the option to opt out of receiving unwanted marketing e-mails. If the e-mails you receive don't include an unsubscribe link you can make a complaint to the Information Commissioner's Office. For more information you can also phone them on 0303 123 1113.

In your complaint you may want mention that One Poll Cash Back website requires people to enter their name and e-mail address just to find out how the website works (and presumably have their details added to a junk mail list). This is a breach of the Data Protection Act 1998 (which is also enforced by the Information Commissioner's Office). The Act states that organisations should process personal details "fairly and lawfully", "for limited purposes", and that the information collected should not be "excessive in relation to the purpose for which they are processed". One Poll Cash Back appears to be breaching all these principles. It's hard to believe the company is actually registered with the Information Commissioner's Office (its reference number is Z7981900).

Also worth mentioning is that One Poll Cash Back has carefully hidden its terms and conditions. You can find the terms via Google but from the website's home page there's no link to information about how the website works. Interestingly, the terms and conditions do mention opting out; point 10 (of 51!) reads: "[hellip;] Your email address will be used to send you regular Rewards Program member's [sic] offers. You will be given the option to opt-out [sic] of receiving these members newsletters."

Finally, there are two lessons to be learned here. The first is to never ever sign up to websites like these. If you can't find a website's privacy policy, or if you don't quite understand what you're signing up to, you really should not be handing over your personal details to greedy marketeers. Instead of trying to save a couple of pennies on buying things from chain stores you'd be better off buying locally / organic / fair trade.

Secondly, if you do need to give your e-mail address to a potential spammer you should use a separate e-mail account. E-mail accounts are free and easy enough to set up; keep one for relatives and friends, and another to sign up to things. That way you keep your private e-mail account private, and at any point you can delete the spam account (once you find the spam starts taking on monstrous proportions).