I have asked and answered a few questions regarding Selenium on Stackoverflow. I think we should move those to this site. When I flag questions and try to move the sqa site is not available for choosing. Where/How should I contact someone to add this feature?
First off, if the question is on-topic for Stack Overflow (that is, a programming question), it doesn't have to be moved. In fact, moving older, answered questions to a new site that's still in beta can be a bad idea: they don't necessarily benefit from the additional attention (if the answers already given are adequate), and don't necessarily benefit the new site (by providing an opportunity for new users to post answers).
That said, there are scenarios when it's appropriate: if the question is off-topic for SO, if it hasn't attracted any good answers, then you can flag for moderator attention and suggest that it be migrated to this site (as glowcoder notes, moderators can migrate questions to any site on the network). Be sure to include your rationale for migration, so the moderator responding to the flag doesn't have to guess at it.
There is a difference between 'voting to close' and 'flagging'.
If you feel a question should be moved here, you should use the actual "Moderator flag" feature. A moderator is able to migrate a question to any Stack Exchange site. The ones you see on the off topic vote-to-close screen are simply the most common ones to save moderators from being completely overwhelmed.