Hi sorry it has taken me some time to get back, i have turned on reply notifications now.
For porting you can choose these guys -> http://www.linuxgamepublishing.com/
they can also publish it via their website, which will then be seeded through to their resellers (more exposure), have a chat with them.
If they are a no go then try ryan gordon -> http://icculus.org/
(he is the guy porting Aquaria to Linux). Also means more exposure as he is a well known name in the Linux community.
I have also made a post asking for help for you on Ubuntu forums which i would post a link to only i got this error "Your message contains too many URLs. The maximum number of URLs allowed is 2.", can you up the forums limit on urls posted please? I basically told them the story and asked them to either PM you or to email the webmaster email.