There is nowhere to get quality coax in Anne Arundel. The closest you could come is purchasing thru one of the 2 Motorola shops, and having them pass along the shipping cost, then tacking on a bit for themselves. I always make the drive to Gaithersburg myself.
I agree on The RF Connection as cited above. They are a great outfit. I've been buying all my coax from them for quite awhile. They'll build a coax with any type connector you might need and do it professionally - plus ship it to your door if you don't want to go to them. They also carry just about every adapter to change from one connector to another that you could think of.