prufrock is right, Stephen King's house is locally known as the William Arnold House.
I believe the three main hospitals are the Eastern Maine Medical Center, the St. Joseph Hospital, and The Acadia Hospital. I also believe they're all about equi-distant from the William Arnold House (~2-3 miles). The
Penobscot River is the primary river that runs through the city. There may be smaller ones but I don't know of them. Hope this helps!