Where to buy in LA or Las Vegas. or online?

I'm based in the UK, but am flying out to LA and then onto Vegas to shoot some b-roll footage with my 5D MkII but I need quite a bit of kit.

I've put together a list of what I'm after:

External battery pack,
Monopd and fluid head,
Canon 85mm f1.8,
Extra Memory cards,
Zacuto viewfinder or equivalent.

Where would be the best place in either LA or Vegas to pick up the gear or would I be better buying online and having the gear shipped to my hotel? (I will need to check with the hotel in advance to see if they'll do this kind of service!)

Cheers

Buy from B&H in Newyork and have it shipped to your hotel. great prices, great service and no sales tax.

In LA, there is a photography chain store called Samy's. They charge close to factory retail price.
Canoga camera is nicer and cheaper. Another store is BelAir camera it too charges close to full retail price. You can search their site and see, but samy's probably has the best inventory.

I'm not sure if stores ship to hotels so you should check with the online stores first.

Thanks for the tips I think a trip to Samy's and also Filmtools, which ohter have recommended, will be one of the first things I do when I arrive.