English Alphabet Flash Cards - 1940s reproduction of a childrne's french book - from "Touch of Europe"
A is for Apple Vintage Flashcards - 5x7 - Set of 26 - from "prettylittlestudio" on etsy
For something a little different (and tongue in cheek) - Nerdy Baby ABC flash cards
from "electricboogaloo" on etsy
Alphabet Letter Photography from "alfabetfotos" on etsy
Apparently these images / letters are the result of four years of "letter harvesting" excursions in 3 countries and 15 states. You can check out Michael's full collection here
"Now I know my ABC's, next time won't you sing with me"