Pinewoods Camp folk music week (Aug. 27-Sept. 3 this year) is a great week in a lovely setting. This year's lineup looks particularly interesting--a great mix of styles, and both instrumental and vocal focus, depending on what floats your boat. Follow the link above to get details. I believe tuition for the week, which includes everything, is just over $700. People are friendly, there's loads of group singing--both built into the day's schedule, and informal after-hours stuff--and formal classes (two in the morning and two in the afternoon, your choice). As to the facility, downsides are not enough bathrooms and showers close to the cabins, and a really long schlep to unload your stuff at the beginning of the week (fine if the weather is good, but a real royal pain if it's not). Upsides, in addition to the consistently wonderful teaching staff, include the gorgeous natural setting near Cape Cod, two swell "ponds" (think "lake" if you're not from New England) to swim in, and really good food.

Augusta is on a college campus and always feels more formal to me, and there isn't the added attraction of nature surrounding you, but they always have wonderful faculty and good singing. One word of warning: BRING AN ELECTRIC FAN FOR YOUR ROOM!!!!! West Virginia can get stifling hot in the summer, and the dorm rooms can be like ovens.
Cheers,
Kathy