1. Atlanta is an amazing experience. Every team should be able to experience it at least once.
2. I'm not aware of any travel packages. Try looking at
http://www.travelocity.com/
http://www.expedia.com/ for deals. Or it may be possible to negotiate a deal or sponsorship from one of the airline companies
3. As of now the competition is most likely held on april 17 - 19. This may change because of the toronado, but this is extremely unlikely.
4. I believe the registeration cost is $5000 US, someone confirm this. Also, there will be hotel and food costs as well as some miscellanous costs.