Two overnight options to look at. There are a lot of other places in the area, depending on if you are interested in more cost effective options, historic areas, or B&B's.
House Or Rental
Caboose Farm
14754 Manahan Road, Sabillasville, MD 21780
Fully furnished farmhouses to rent with multiple bedrooms; great for multiple guests. They are only 15 minutes from the venue.
Hotel
Best Western Historic Frederick
420 Prospect Boulevard, Frederick, MD 21701
Great for individual or small groups. About 30 minutes away from the venue.