The company says its name is
GPRX
with an address of
603 Village Blvd
Suite 103
West Palm Beach Fl, 33409
But White Pages and Yellow Pages searches reveal there is no such company within 100 miles of West Pal Beach FL 33408.
To get off the company’s mailing list, it want’s me to complete a form of my N&A and phone number but no mention of my email address.
How can I thwart these bastards? (They market health products - vitamnis, etc.)
Opt-out links from companies that spam (excluding reputable opt-in services that only spam you if you ask them to) are useless. You won’t get removed from their mailing list, and they’ll sell whatever information you give them to other mailing lists.
Your only real hope is to install a spam filter/proxy, like SpamPal or the like, and have your E-Mail client automatically sift through your spam.
Oftentimes, the “suite” will be a mailbox in a MoneyMart or copy shop or something like that. I’m thinking of getting one myself; I was going to go to Mailboxes Etc, who advertised being a place to do copies and receive courier deliveries, etc, but they suddenly became the UPS Store and now I wonder whether FedEx will drop off there. 
I get my stuff by Canada Post.
The street address you gave applies to http://www.gprxstore.com . A quick background check of the URL reveals the site registration is a private registration. However, a more careful check of the site reveals under Terms that the site owner is in Washington State under the name Neriah Naturals, LLC. A Google Search reveals more info here —> http://www.wpb.org/construction/reports/new_business_report/2007/01_January.txt (search under the LLC name.) However, a search of the Washington State corporations directory reveals Neriah Naturals, LLC is not registered in Washington.
Bottom line …
Set up a filter in your email client to direct all emails to trash.
Beyond that, there isn’t much you can do.
Duckster, you’re living, breathing jaw dropper. How you get your information I’ll never know, but I will always be amazed, impressed and agape. Thank you very, very much.
I recommend Spam Assassin as it’s 100% guaranteed effective.
Only in Russia, unfortunately.
Thanks, Tuckerfan.
Welcome! 
Seriously, finding the information is relatively easy to do if you have the tools. It’s not rocket science. The only tools I used are this little search engine, DNSStuff.com and the Firefox web browser. (No, I’m not slamming IE this time around. However, using a different browser sometimes changes things a bit – I have no idea why – and your results might not be the same as mine.) So here’s a Search 101 course for you. It doesn’t always work as one would hope, but more often than not you can glean a considerable amount of information. It also helps to think outside of the box.
You provided a name and a street address. A quick and simple search of GPRX found the web site. A check of that site’s Contact Us confirmed the address you provided. (Next time, provide the URL so one doesn’t have to search for it! Otherwise, one can be lead down a different path that, at first appears to be a dead end.)
OK, with me so far?
Now let’s find out who owns the domain name using http://www.dnsstuff.com/. DNSStuff has lots of free tools to find out various things. In this case, the WHOIS Lookup is your first port of call. Plugging in the site address reveals the site sits on a GoDaddy.com server, but it’s registered using GoDaddy’s hidden registrar, Domains by Proxy. Dead end. You will not get much of anything at this point.
OK, let’s go back to the suspect web site and see what they have to offer. Quite often a site owner leaves just enough information in other areas of the site that we may find another door to open. In this case, we did. The site’s Terms web page offers a wealth of identifying information.
The site owner not only lists a name, Neriah Naturals, LLC, but any disputes will be under the laws of KIng County in Washington. A check of Washington Secretary of State Corporations web site says Neriah Naturals, LLC is not registered there.
Now back to Google to search the LLC name. There is nothing of substance relevant until page two of the search where one finds business names and addresses.
This is where I stopped. Had I searched the Florida Secretary of State’s Corporation data, Neriah Naturals is a Florida LLC, complete with names, addresses, etc. BTW, Neriah Naturals, LLC is owned by another LLC.
If you had provided the email headers, there is a wealth of information there to be explored as well. But as I said the first time, set up a filter to send all their email to trash.
Wow!
I Snagged your treatise and will refer to it regularly. Might even join DNS.
Thanks again. I have a feeling Cecil’s looking over his shoulder.