Don't worry; you can do it. We just booked last week. Days Inn, 300 Spring Street has 2 double beds for $130 night; split it 4 ways and it's more than reasonable. Embassy Suites also had rooms available if you were a gold card holder; they were more expensive but you can fit more people per room so check it out.
Air Tran and Delta both fly direct. We got ours for less than $180 per person. We are flying in to Atlantic City for the trip home; it was a bit cheaper. Amtrak is inexpensive per person but be warned that a 16 hour train ride really messes with your head. It's better for the trip home! If driving is your thing then check the website for Penguin Rentals in Pennsville NJ. We rented a 15-passenger van from them for our trip to Rochester NY. It was $400 with unlimited mileage. Tell them South Jersey Robotics sent you!
If you have a van then you can check out the hotels outside of Atlanta, or near the airport. Also look at stonemountainpark.com to see if they have cabins available.
So for our trip, planned last week, for 3 people we came in right around a $1000.
Keep us posted! See you all in Atlanta!