How to find my perchased history?

Hi Ken, 
In your profile, please navigate to Download tab, you can keep track of your current subscription details. 
Meanwhile, please consider to take advantage of Xmas offer to have your Developer subscription renewed. You can check out further details on our Xmas discount via: https://www.ubertheme.com/magento-news/celebrate-christmas-with-ubertheme/
Regards,
An Nguyen