Just off Rte 355 in Gaithersburg, in the bottom floor of the Kaiser Permanente building, you will find one of the nicest stores around for stampers, scrapbookers, and other paper-crafty types!
While not as large as an AC Moore, or Michael's, the Rubber Chicken has a whole lot to offer. Their inventory of rubber stamps is HUGE and extremely varied and if they don't have what you want, they will find it for you and get it.
The thing that really makes the "Coop" special isn't it's huge supply of stamps, papers, and accessories. It's the employees (and the classes they offer) ! If there is a technique you're having trouble with, or a design you just cannot get quite right, the ladies at the Rubber Chicken can help you out! They offer free help which is just priceless and are just a nice as can be.
There are always a wide variety of classes being given at the Rubber Chicken, and you can see examples of the techniques you will learn and the cards you will make on display in the shop -- and sometimes on the website as well. Check them out on rubberchickenstampart.com. You'll be glad you did!