Thank you for your reply, I am quite familiar with the theory of suspended chords and such.
I just didn't understand why an A Major chords |002220| was listed with the name Amsus4. I can only assume that it's from the old chord theory, indicating suspending the minor to a major. Perhaps some now forgotten way of playing an A Major chord in a key with a rightful Am chord.
Who knows really?
There are a lot of old chord theory oddities I've encountered in older books and with older players. Seemingly before chord theory adopted it's modern ruleset.
Anyway, thanks for your response. I just thought I'd bring this to the attention of someone.
P.S. (When I said the chord should be an Amadd11, I meant that my understanding of translating the name "Amsus4" would be of breaking down the name, Am + sus4. Changing the "sus4" into an "add11" for the obvious reasons that you can't have a minor chord with a sus4. As that defeats the purpose.)