Stop the SPAM

I would like to offer people an opportunity to become a registered user. I could then track their interests, and we could dialog. But any automated process for requesting an account opens me up to getting spammed (or hacked). I am fortunate that my hosting service, InMotionHosting, allows me IP Deny; I can enter an IP or range of IP addresses, and anyone with that address or within that range will be denied access. However, it is a pain. And unfair to people with legitimate needs. I'm looking into participating with StopForumSpam; a service that lists names, e-mail addresses, and IPs of spammers. So, if/when I get a request, I can check their list. Or if it is clear the user is trying a hack (e.g., using the name of someone from my site(s) and an e-mail that is not legit), I can add them to the "list of shame". Not the best solution, but better than the alternatives.