The Dive Shop on McEver has a Valentine's Day special going of buy 1, get 1 free on Open Water instruction. That's a savings of around $300. Bear in mind that you'll both need to buy mask/fins/snorkel/boots and at least 1 instruction book package from whichever certifying group you with (PADI/NAUI/SSI). You will also both still have to pay for the check-out dives that occur in open water afterward. The shop is near Gainesville, GA. They usually do check out dives either in the springs in Florida or the flooded quarry in Tenn.
Regardless of where you decide to do you confined water training, one option to consider is to do a checkout referral. This would allow you to go to another certified instruction facility and do your open water checkout dives. I did my confined water at TDSOM and did my open water checkouts at Stuart Coves in the Bahamas. I already had that trip planned, so it made sense - otherwise that is a considerable extra cost to just getting certified.
Edit: yep - they still have the special going -> http://www.thediveshoponmcever.com/component/content/article/2-scuba-courses/35-diverx2