What might help is listing specific things that people can do to help out. For example, don't just say "Go find us more players", but maybe something like "Please go contribute to this thread on the Bay12 forums: (insert URL here)" or "Vote for BattleMaster on this poll: (insert URL)". That way people can maybe click a link and contribute to the effort.
Not sure how applicable this is, but maybe if it can be done, then it would make it easier for people to contribute.
