This is not something we can do for you legally. Here's what to do...
Login to your BlogPress Domains account (Not the same as your blog login)
Click here to login: http://domains.theblogpress.com/ (if you don't have an account, you can create one.)
Click the link to Transfer Domains and follow the steps provided. (If you have any issues with transferring the domain, call the support number (480) 624-2500 - this is the support team ONLY for domains. They cannot help with your blog. That's us :))