Here are the ones in and around Gettysburg that I know, from highest price to lowest price:
1844 Antrim in Taneytown, MD (about 15 miles) - beautiful sprawling Select Registry inn, with several outbuildings with guest rooms. Excellent restaurant and the rooms are upscale. Rooms are $200 to $400 and I think include a continental breakfast delivered to your door - you may have to pay extra for a full breakfast in the restaurant. I have never stayed but I have eaten there and toured the rooms - they are lovely. It is more like an estate inn than a traditional B&B.
Doubleday Inn B&B - perfect location right on the battlefield in Gettysburg. Lots of history stuff there, and great grounds for walking or touring the battlefield. Rooms are $135 to $195, I think, and include a full delicious breakfast. Nicely welcoming hosts and I like their dog, too. I have stayed there and was very comfortable and well-fed. More of a traditional B&B. My room was the Cutler with a sunset view of the battlefield and a very spacious bathroom.
Beechmont Inn in Hanover, PA (around 15 miles) - also a more traditional B&B but some of the rooms have whirlpool tubs. A Select Registry inn and the innkeeper Kathryn is seriously one of the nicest human beings on the planet and an excellent cook to boot (she is one of the Eight Broads in a Kitchen). Rooms are $130 to $170 and include a full breakfast. There is at least one fine dining restaurant within walking distance (the Sheppard Mansion). I stayed in the Birch room.
Hope this helps. It might be worth noting that Quite the Stir in Gettysburg is an unhosted cottage rather than a traditional B&B..