According to ANN, Seven Seas is going to publish an omnibus version of the Strawberry Panic! light novel series, which will include the third and final installment that hasn’t been published in English yet. It will be published in June 2011 for only $14.99 according to the official press release (found here).
I really hope they do this for Pita Ten as well since it only had one more volume as well! It would be awesome to see more of Ballad of a Shinigami too (though that’s 12 volumes total). No word on either of these yet though.