On amazon http://www.amazon.com/Xbox-360-Month-Live-Gold-Card/dp/B0029LJIFG/ref=sr_1_1?s=videogames&ie=UTF8&qid=1301263172&sr=1-1
My Live account expired last night, so this is good timing. Last time I only paid like $35 for a year, but this is the best deal I'm seeing right now.