The best way to get there is to fly into Atlanta and then rent a car to drive to Acworth, which is about an hour away. You could take an Uber/Lyft/Taxi instead, but you will probably want to have a car during your stay as there is no real public transportation, so if you want to explore, you'll want a car.
There are many hotel options in the Acworth area. Here are 4 that we recommend and are all about 6 minutes from the wedding venue and 10-15 minutes from our house. We also recommend looking at Airbnb and VRBO as there are quite a few great houses in the area.
If you prefer to stay closer to Atlanta proper, it is about 30 miles (45 minute drive) from Acworth. There is an abundance of hotels and great places to stay there, but you will have to travel a little to get to us.