Man, their system is strange. I actually followed the link from the newsletter I received from them. But when I put in my E-mail to "Confirm Details," it insisted I wasn't signed up and made me sign up again. And indeed, it sent me
another welcome to Tor.com's Free eBook club E-mail after that. (Last one is from July 11th.)
Still, it's free, so I'm not complaining all that much. I just find it strange.