I was seaching all over the web and can't find a thing.I want 12-15 inch THICK plastic worms . I saw some big soft plastic snakes that some in tubes a BPS but they were $4.50 a peice . I dont want normal 12'' culprit or zoom worms ,the biger the thicker the better.

I am not much of a soft plastics guy, but have you looked at Rubber Eels?  I think they are typically used for SW Striper fishing.

http://www.dzinelures.com/critters.htm

i've used those snakes. the body is pretty thick, about 1/2 to 3/4 of an inch, but only half of the body is thick, the rest is just a ribbon tail.

i know they are snakes, ie. topwater, but you can request them in the non-floating versions.

You might have to look at some kind of saltwater lure maybe.  Or just use a bike tire tube ;D

check the musky shops online...rollie and helens or thorne bros.