Sorry you had a bad time, but I wouldn't give up yet....
Were they at gobbling all around you, or just clucking & yelping? And how was your calling? Good, fair, poor? You need to sound as realistic as possible. Also, those Easterns are not as vocal, so you actually want to call very very little - a lot less than you want to call, with Easterns such as are in Pitt Co. You may have been calling too much and/or unrealistically. With easterns, you want to yelp a little, followed by a cluck or 3, then shut up for 10-15 minutes and see if they come in, then repeat. Also, you want to mix it up. If they don't come to your slate call, they may very well come to your box call, push call, or mouth call.
Also, they often get henned up real early on in the day. If you don't get one between 6 am and 7:30 am, then you're probably NOT going to get a big gobbler that morning. However, in my (limited) experience, if you're satisfied with getting a small jake, then keep on calling sparingly until 8:30 or 9:00 am, because a jake may come in silently - they don't want to gobble and get their butts kicked by a big tom. If, OTOH, you want a bigger one, quit and go take a nap about 7:30, then settle back into a spot around 11am or noon, because by then, most of the hens that the gobblers were with will be sitting on their nests, and the toms will once again be back out looking for stray hens to breed with that they missed. You can possibly get one this way anytime during the afternoon. Then, toward the evening, around 5 or 5:30, if you know where they're roosting, go in and set up again near the roost, on a likely ingress route, and call sparingly.
As for rain, if it's raining hard, they'll just stay up in the roost until it stops or lightens up, so that couldv'e been a problem. If the wind was high (more than 15-20 mph), then they are not going to be in the woods - they will move to open fields and feed there, so that they can hear & see predators coming. Turkey hunting SHOULD be one of the most enjoyable types, because they talk back to you. Did you have any of them "cut off" your yelp or cutting calls with a gobble? That's how you know they're hot to trot and probably coming in - if they cut you off with a gobble then shut up and let them come in! If a gobble sounds closer than the last gobble, you should not make any sound at all, because they're coming in, and you risk sounding unrealistic and making them get scared and turn. So if they're coming closer after calling, you should ONLY call if they suddenly sound farther, like they've turned. You should have a decoy or 2 out to give them something to entice them once they get close - did you? The best decoy is a young jake mounting a hen. This will PO the big daddys.
Turkey hunting to me is a lot more fun than deer hunting, because they're talking to you, you don't have to control your smell, it lends itself to buddy hunting (one calls, and one shoots), and it's a much higher success rate. Did you go opening weekend? That's the best time. Turkeys are stupid on opening weekend, but they quickly learn that they're being shot at, and get real quiet once hunting pressure is applied. This was my 2nd year to hunt them. Last year got 2 birds on 3 weekends. This year not as good - got 1 bird on 3 weekends. Mating season was *completely* over by the very last weekend - I did not hear a single gobble - they were clucking all around me, mostly hens I'm sure, but would not come to my calls.
Also, were the boys being still? Turkeys can see movement a lot further away than we can, and see in 330 degrees around them. Also, where to set up is very important, so that you make it as easy as possible for them to come to you. PM me and I'll try to hook you up for next year in Western OK for some Rios - they are a lot dumber and more vocal.
As for calling, a good slate call with 2 strikers is the easiest to make realistic clucks and purrs with - one wood striker for best sound, and one acrylic striker for if your slate gets wet (it will still work). Box calls are great for yelping & cutting, but harder to get realistic clucks and purrs from. I'm not good with a mouth call, but my yelp is decent, and of course you can do a mouth call without moving your hand when they get close.
Oh yeah, and as I'm sure you're aware, knowing where they roost if possible almost guarantees a successful hunt, if you set up correctly, into their flydown area. So scouting pre-season until you find a roosting area is extremely important if you want to up your likely success rate from 60% to 95%, let's say. I sure act like I know a lot for only hunting 2 seasons, don't I? Well, I did buy a book and 2 videos on the subject.
Also, on the comfort thing, there is no reason to be uncomfortable, if you're just willing to haul a bunch of crap into the woods. I am very comfortable and keep the rain and ticks off of me, not to mention make myself hidden to the turkeys, using: a doghouse popup blind that folds up like a car sunshade and is worn as a backpack into the woods, and just a regular camp folding chair, either brown or camo color - just carry it with you, and finally this product allows me to sit quietly and comfortably with my shotgun at the ready while I am calling:
http://www.hunterspec.com/Updateable/update_display.cfm?pageID=1906&categoryID=33