My home is in Portland, Oregon and my online orders mostly go to Western Bike Works/Bike Tires Direct (Western being the store front for BTD) and Universal Cycles, the latter has to have one of the broadest parts selection in the world. Both stores are located in Portland so I save shipping costs on small orders picking them up when in town. Both also have loyalty discount programs.
But for over a year I’ve been living in Hawai’i on an outer island and find myself frequently ordering from Amazon using Prime free shipping. While in Hawai’i I’ve been building up my Dahon MU for a European tour and have been ordering some specialty parts and 20 inch “tyres” from SJS Cycles half a world away in England. I mean not every online suppliers has a 28 hole, 74 mm wide front hub on the shelf.
https://www.westernbikeworks.com
https://www.biketiresdirect.com
https://www.universalcycles.com/
https://www.sjscycles.co.uk/