I have two options/suggestions. for used sails there is a loft/used part store in Annapolis Maryland that is awesome Bacon Sails. I could not find a used sail that would fit my boat so I just broke down and had a brand new set made. Moorhouse Sailmakers did my sails and I couldn't be happier with them. I did most of the dealings over the phone and Skip is a very knowledgable guy and I came out with an excellent set of sails, he gave me a much better price then North or any of the other big boys.
As an added tip, I use him for all my sail cleaning and repairs, they do it on site and have a fast turn around, I ship UPS and it is great. Not to seem overzealous, but if you could feel how well my boat sails right now you would be too.
As John mentioned, Jack Wedekind is on Terryille Rd in Port Jeff Station. Super nice guy. i haven't bought any sails from him but he has repaired main main, repaired my bimini and made a new Dodger. Good work, good prices.
Some other, big name places include North (Chris Bunke is the sailmaker) and Doyle (Mark Washeim) in Huntington. I have bought 3 sails from UK Halsey in City Island. Tom Nye is the sailmaker and I think he's a great guy (but I'm prejudiced since I've bought sails from him).
You should visit Jack Wedekind and call the other guys to discuss what you want and get prices.