To retrieve the web pages, and parse them for email addresses you should take a look at the following modules:

1. LWP::Simple - To grab the web pages.
2. HTML::TokeParser - To parse the HTML.
3. Email::Find - To find email addresses in plain text.
4. Email::Valid - To validate the email addresses.
5. Mail::Bulkmail - For sending out emails.

As for mail addresses, they'll be a lot harder to find due to the number of possible formats they could be in. Try looking for keywords in certain orders (e.g. number, street, city). This will be very difficult and unless you're willing to spend a lot of time on it you probably won't have much luck.

Now, as one of our illustrious members articulately observed, SPAM is bad. It is also, in all probability, not the best way to go about obtaining new customers. Chances are you'll only get blacklisted and obtain a less than desireable reputation. So please consider your methods carefully.

And some extra reading:

• Why Unsolicited Bulk Email is Bad Business
• SpamAssassin

That said, I find the Anti-Spam fanatics far more annoying than spam. Flaming a few possible (there are many false postives) spammers on a Perl forum won't do anything to solve the problem. If you want to be productive, write better filters.