Account blocks are usually set by the local admins, and not by Wikia. The name of the blocking admin should be on the block notice you received.You may be able to contact the blocking admin by leaving a message on your user talk page. This is still editable for blocked users (on some wikis) and changes will usually be seen by the other contributors to the wiki. Your user talk page is found by following the "my talk" link at the top right of any page.
However, if this talk page option is not available in your situation, then the best advice we can give you is to wait the block out or join the community at another of the many thousand Wikia wikis available.
If you feel you still need to discuss this block further with Wikia staff, please contact us here.