Well, first off, if you heard birds in the area-then obviously it's a pretty good area. Keep in mind the birds are still mostly in "winter mode" and are likely to have moved by opening day and right now they are not "hot" and answering back to calls. I'd suggest you really try to get back out for another scouting trip closer to the opener. Unless you have only one trip you can make, i'd certainly plan on going on the opener and starting the learning process. (It's a long one on turkeys) You can get surprisingly close to birds in the dark, but I'd certainly have a plan in mind the night before (try roosting birds if you can) so you don't stumble under a roost in the dark and spook them off. Not a whole lot of reason to randomly set out decoy's if you havent heard or seen birds in an area-they arent like ducks where you can draw them in to a spread of decoy's. For me, the biggest key to turkey hunting is prescouting and getting an idea of what the birds you've spotted are doing. Keep in mind that birds close to roads have probably already been spotted and you might get there opening morning to find a full parking lot of other hunters. Try to find birds a little more isolated where you might have a better chance of being the only hunters on the flock. Good luck-I'm sure you'll enjoy the hunt and don't get frusterated if your first couple of try's don't work!