In September there will be a "Transfer to Commons" drive at Wikipedia:WikiProject Images and Media/Commons/Drive Sep 2011! I will be both participating and reviewing transfers. You can ask questions about the drive here.
This guide is a condensed and streamlined version of Wikipedia:Moving files to the Commons. It is strongly encouraged that you read that document in its entirety before you begin making transfers, as it contains the full instructions, a ton of good advice, and links to tools that have been created to make transferring easier.