Better late than never! First tri on Sunday, I'm already registered, but there was no mentoin of a USAT membershoip needed. How do I find out if I need one for this event? It's the Tempe Multisport Challenge in Arizona.
There's a website for the event and to the best of my reading ability I believe they say that they are not a sanctioned event this year. See the FAQ's on the site regarding insurance.
if there's no mention on a website, they will normally ask for your USAT card at race registration. If you don't have one, usually there's a one day license for less than $10.