My older (1950) dictionary lists 'alright' and says it's an 'unaccepted' spelling. I've always seen this around very commonly, and can't see any objection to it. Why all right but already?

'Alot' is new to me; I've seen it only very recently, on the Internet; except that I rather fancy an American pen-friend of mine also used it years ago, and it struck me as odd then. I doubt I've ever seen it in print. I regarded it as a puzzling spelling mistake until I worked out it was a current Americanism. There is no true precedent for it (*abit, *amoment) where the 'a' is the article, but plenty of eye-precedents, such as aloft and ago and aback.