Oddly enough, the word `emailed' is actually listed in the OED; it means "embossed (with a raised pattern) or perh. arranged in a net or open work". A use from 1480 is given. The word is probably derived from French `'emaill'e' (enameled) and related to Old French `emmaille"ure' (network). A French correspondent tells us that in modern French, `email' is a hard enamel obtained by heating special paints in a furnace; an `emailleur' (no final e) is a craftsman who makes email (he generally paints some objects (like, say, jewelry) and cooks them in a furnace).
There are numerous spelling variants of this word. In Internet traffic up to 1995, `email' predominates, `e-mail' runs a not-too-distant second, and `E-mail' and `Email' are a distant third and fourth.