Amazon: I'm pretty sure they never sell Nintendo hardware themselves, yet for some reason it seems many people expect them to sell Switch.
GameStop: people are telling me they don't ever do hardware preorders online- only in store. Is this true? I planned on going through GS, but I suppose not.
Best Buy: I honestly just hate their company- they can be careless and I still bear the scars of being screwed by them with my Majora's Mask edition N3DS preorder.
Target/Toys R Us: neither do online preorder, or preorder in general afaik.
So, unless somebody can assure me that Amazon will indeed sell Switch or GameStop DOES in fact let you preorder hardware online, I'm going with Best Buy, which I swore I'd never do again. God help me.