Another reputable source for used cameras/lenses is
KEH.
B&H is closed every weekend for the Sabbath as well. Adorama is another good NYC bricks & mortar/online shop. An interesting thing, I'm starting to shop around for a D200 and it's the same price at B&H and Adorama. But, Adorama is selling the Nikon extended warranty for quite a bit less, so it pays to compare.
If you want to check out how much bags will hold, check
here
LowePro announced some new bags recently that look nice, the Vertex line.
Another nice bag that I'm prob gonna get is the lineup from
ThinkTank. They too just announced a new line, called "Urban Disguise". Thom Haga has a nice review
here 
