Get a map of the reservoir that the Corp puts out. They have all of the dispersed campsites listed on the map. Of course for a campsite with amenities you'll have to go to either Dent Acres or Freeman Creek. Like others have said the reservoir is down, so you'll have to hike through some sand/mud from the water to either camp or hunt up from the boat.
While not extremely popular, turkey hunting from a boat is a fairly common technique people do the first 2 weekends of the season. And of course hunters gravitate to the more milder terrain. That being said roosting a tom from a boat before dark with a boat can allow you to cover lots of ground. Don't overlook fishing in the morning along the shoreline until you hear one, and then changing pursuits.
If you can go during the weekdays you'll have a lot of ground to yourself. I'm not giving away any secrets here, so try Canyon creek, Freeman Creek, and Elk creek for both fish and fowl.