This is a link to the Georgia Law regarding HOA. First thing to do is to read it.
Second, when you bought your house, if it was in an area subject to a HOA, you should have received a copy of the Declarations attached to your copy of the Title Insurance/Search. It would have been provided at closing. You need to read this.
Third, most HOA/Declarations provide that when the build out reaches the point where some majority % of the lots are sold, that the board of the assn. reverts to control of the homeowners. There should have been director elections and some homeowners should already be on the board.
Most of these developments have some sort set of agreements with the local building regulator about issues such as drainage, amenities, etc. which were conditions placed on the developer in order to get the master permit. This should be on file with the county. If the developer is not living up to the agreement, the local building officials should be contacted.
All this together should help your group of owners understand the situation and whether they will need to seek legal advice about resolving their problems.