Alphabet Truck is the photographic work of Eric Tabuchi. He has done plenty more interesting stuff, including Twentysix Abandoned Gasoline Stations, French Countryside Skateparks and Road Signs. See here. I used to have a postcard of one of his images, I now realise, but it fell down the back of the fireplace, dammit.
I've put this up for your delectation, because words are made up of letters so by default Words & Fixtures likes letters as well as words.
(Thanks to @MancLibraries, BTW, for flagging this up on Twitter.)