Someone has signed up using my email address

Eventually this person will wake up and make the correction but until then  just Mark them as spam so the emails go to the spam file  and ignore them or  block the emails.   At the bottom of the email there should be an option to unsubscribe to the marketing emails.  

Well they signed up in March and I'm still getting emails. When I click the unsubscribe link, I am asked to log in to manage my email preferences. Why can they send emails out without ever confirming the email address is real? How can I get this fixed?

There is nothing you can do to fix this anymore than you can stop getting junk mail in your mailbox  ...just  send the emails to spam, report them as spam and or block them using the email provider.