I second the recommendation for Whole Foods, but would also suggest giving Wegman's a try. The folks in the white coats seem to be well-trained and very willing and able to cut the roast or other items you may be looking for.
I would also recommend trying a halal butcher (my personal favorite is Amity Halal Meat & Grocery on Lee Highway
http://www.amitymeat.com/index.html). May not be the first place you think of, but the meat beef, lamb and chicken is very fresh and the service is friendly. They also have the best feta cheese I have ever eaten and their olive prices are much less than you will find at larger stores. It is, however, an ethnic market which caters to a wide variety of people.