Here are some of my favourite stores to buy backpacking gear online. I would love to hear comments from other readers on where they shop and recommendations they have.
I like this place a lot. They are a store in Oregon that carries a lot of ultralight gear. They have a great selection and knowledgable staff. For me based in Seattle, they are on the UPS route, and so shipments arrive really quick.
Another great site, fast shipping. They carry some things that Backcountry Gear doesn't have.
We have a big REI store just a mile away, I don't really order online, but I do shop there for odds and ends. They have an amazing selection of things.
Pro Mountain Sports
Great tiny local store in Seattle. Good selection of ultralight gear. I have never ordered online from them, so can't comment on their shipping speed.
I have a great store called Montbell for ultralight gear. They only have one brick and mortar store in the US which is located in Boulder, CO. They have a great website and ship in the us. They have a great tarp called a tube tent (I think). It is not on the web site though. $75 for the tarp at just under a pound and the thing is huge. It has a lot of tie down options and even draw cords for different configurations. Great light weight clothes, although not real cheap. Great gear and sleeping bags. They have an inflatable pad pillow combination that is worth checking out. They carry a lot of other things that the majors don’t carry. I have a hard time buying things online. I like to touch and play with it before I buy it. I just happed to run across their flagship store in Boulder and was really impressed with their gear and clothing. The staff was really cool.