The "word for horse" redux

Dear List:
Everybody knows about the myth of the Trojan horse. Does anyone know
where I could find the earliest printed refference to the "Trojan
Horse" ? (no it's not the llliad, its not even in the Illiad as is
commonly believed) Many myths can have more than a kernel of truth to
them what was the origin of this one?
I was curious why the Achiaen League would to build a horse. Why not
any number of other animals? Why specifically a horse?
I really enjoy this list. I apologizethat I have no training as a
linguist and that sometimes my approach to the problems discussed is
rather oblique.
All the bes