I have an area that is 100 X 10 is there any spray out there that would let me use the heads on only one side. I'm looking for something like a rectangular pattern in the 10 x 15-20 ft. range. Any help would be appreciated.

Both Toro and Rainbird make side-strip nozzles that can cover a 9x18 area. Toro's is 9SST, and if you give it extra pressure, like 50 psi, then the pattern becomes 10x20, which should work for you.