This is a peer support forum where Volunteers answer the majority of all questions and only flag those they cannot answer for Staff attention. There is no phone support.
All support documentation for WordPress.com bloggers is at this link http://en.support.wordpress.com The results produced by the searchbox there are from both the support docs and from forum threads.
See here > premium theme support > http://en.support.wordpress.com/themes/premium-themes/#premium-theme-support
Read-access to the premium themes forum is now open to all users so you can search to see if your question has been previously asked and answered there. The premium theme forums are at http://premium-themes.forums.wordpress.com/ with separate sections for each theme.
If you are not successful when searching then there is a link for the specific Premium Theme support forum for your theme under Appearance -> Themes in your blog’s Dashboard, but do note that the premium theme must be active and you must be signed in as the user who purchased it in order to see it and post to it.