In NYC, B&H Photo is the big dog of photography. They have a great web site and decent prices. The store is amazing too - Disney World for the shutterbug.
But it's Saturday. You need a 2 gig compact flash card (which I did) and my local guy was fresh out. Calumet to the rescue. They open on Saturdays at 9 AM. They have nice people who know their stuff and good prices.
They also rent equipment, have a lot of used hardware for sale and they offer classes (for free) in their tiny classroom (reserve early).
I never have trouble parking either - NYC doesn't get up on weekends until 11 (12 on Sundays).
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