I bought a 2005 Dodge Ram 1500 2WD with a 3in body lift and is sittin on 35's. One lug nut is missing from each tire and it is a weird size so I cannot find 4 of them anywhere. I have been riding around with 1 missing on each wheel now it my front left tire makes this winding/squeaking/grinding noise when it i slow the truck down to a stop. Tried tightening the lug nuts moving them around so that the missing one is not always in same spot. Took it to a shop they said wheel was lose they tightened it and gave it back to me and still same problem. Any suggestions? No idea if lug nuts effects this problem or its a bearing or what totally out of my league

 

Sounds to me like someone took the one locking nut off each tire. The size is 9/16 x 18mm (requires a 7/8" socket for install & removal and you are right, MOST auto parts stores do not carry it, but most tire shops do and it's available online all over the place. This is a change from the 2nd Gen Rams which used 1/2" lugs and are available EVERYWHERE...

 

Might have to pay out the @#$ at the dealer for 4 lug nuts unfortunately. I'd say look online but you should really get all your lugnuts on pronto. A junkyard would also be a good place to look.
I'd pull off the tires to check the brake pads, that's the most common squeak when you're slowing down. I'd be checking over the rest of the vehicle as well, it sounds like you might have a sketchy seller here if they sold you a truck missing lugnuts...

 

Hammer hit it on the head. Sounds like they lost the key to the locking lugs and didnt put them back on. When i bought my lugs for my after market rims i had to get them from a rim shop. They were about $30 for a set of lugs and locks.