Sewickley Valley Hospital is a nice size community hospital. I don't know what positions are available there or what starting pay is for a GN.
Allegheny General Hospital is a level 1 trauma center on the north side of Pgh across the river but not far from the Moon Twp area. They have many positions open and hire new grads. They are part of the West Penn Allegheny Health System. They also have a suburban campus which is called AGH Suburban, located in Bellevue, which is extemely close to Moon Twp. It is a small community hospital that has positions open for Peds, ICU, PCU, PACU, and ER. I think they hire new grads, again I don't know starting salary.
Ohio Valley Hospital is not in a health system. It's a small community hospital all by itself. It's in McKees Rocks which is next to Coraopolis on the same side of the river. McKees Rocks is not the best of areas.
Then as someone else aready mentioned UPMC has a lot of hospitals. They are all a little farther away from where you are moving but may offer good possiblities.
Welcome to the Burgh and good luck with your job search.