Finding an online store for outdoor lighting equipment?

not everything but a lot,and they have lots of videos of products and do comparisons

http://goinggear.com/flashlights

http://goinggear.com/zebralight-sc51w-neutral-aa-led-flashlight.html

http://goinggear.com/zebralight-sc31w-xp-g-neutral-white-cr123-flashlight.html

not in the U.S.

http://www.torchworld.com.au/catalog/

If you want potentially more info than you can handle I suggest checking out Candle power forums:

http://www.candlepowerforums.com/vb/forum.php

I can not think of one vendor that covers all the lighting areas that you are talking about, other than REI, but I don't think that is what you are looking for. As for specifics here are my favorite:

Bike lights:
http://www.dinottelighting.com/

Headlamps:
http://www.zebralight.com/

These will blow away anything you can find at your local REI or outdoors store

General Flashlights:
http://www.4sevens.com/
These guys are one of my favorites, and very reasonably priced.

http://www.surefire.com/
For a more tactical approach.

Hope this helps, if you have any more questions refer to the folks over at Candle power forums.

Cheers!

John

Very soon 'Ryan' will come back with a 'I've found this place….'

Been spamming UK forums. I've reported it.

Mountain Bike Review has done an extensive review of bike lights:
http://reviews.mtbr.com/2012-bike-lights-shootout

David