Don't click links in spam--EVER! Even if you're interested in the product. Even if it looks like a legitimate company that just made a bad decision about how to attract new customers.

Even if you don't enter any personal information on the spammer's website, the link that you click to get there may include an ID code that they can use to figure out who came to their site. If you want to check the website out, you need to get there in a way that won't tell them who you are, because once they know you're willing to click links in spam, you become a prime target for more junk email.

To check out the site without revealing your identity, type the address of their webpage into your browser, taking care to leave out any part of the link that could be used to identify you. For example, if the email links to "http://www.hotstuffdude.com/products/hotstuff.php?ref=1384763129438584", enter "http://www.hotstuffdude.com/products/hotstuff.php" in your browser. Do NOT include "?ref=1384763129438584"--it's probably there to identify you. Of course, it could also be a product ID, without which the site won't show you the product. But if their website isn't terribly designed, you should be able to find it by clicking around the site.

If all else fails, and you just can't stand to leave without seeing the product, then of course it's up to you whether you want to click that link. Just be aware of the risks.