I'll sumarize here, though.
This is only for ponies with the "buck" and "prance" bases (who I am authorized to make tack for!) Examples are in the thread itself.
Entry fee is 15GPs.
Prizes are nuts, but may include any of the following: a breeding with Mea Soleil, mystery tack, 10 ponies trained to Lvl 2, stallion breedings, or a mare breeding.
More information at the thread itself.