If it's been 3 months I doubt they'd be able to do anything.
http://us.blizzard.com/support/chart...webform-us.xml
Here ya go. This is how you do character transfer reversals (how you'd get the char back on your account.) Go hog wild.
Only problem is, after 3 months, Blizzard considers it case closed and won't reverse the transfer, most of the time. =/ Give it a try anyway, though.