I live aprox 10 miles south-se of you. I had Buy-Rite windows corp install 12 double hungs, 1 slider and 2 picture windows in my current home. Price - need to know basis. Anyways, the windows are made by Sunrise windows and are very nice. I've recieved complements on them.
Also, do install central air, even without the windows. Nothing is nastier than 95+ temps with 95+ humidity in the summer. In my last house I had central air installed the last year I lived there. I had it (Bryant) installed in october and moved out the following july, so I only got to use it for a few months. It was very nice. My present house has a Ruud air conditioner and it is also very nice. My all means, do get one ASAP.