http://www.livejournal.com/community/paidmembers/13251.html
All paid members can get some free time. Two weeks free, or 2 months if you purchase a 6 or 12 month account.
The reimbursement page is here:
http://www.livejournal.com/pay/claim.bml
Oh, and if you are planning on purchasing more time to get the 2 months, make sure you don't click on the extend 2 weeks button first, you have to go back after purchasing the time.