I played around with the API a few days ago and had the same problem everyone else did. But then I logged out and logged back in, and I was able to find the option to browse 2010 events and post to the 2010 playa events. I started my entry, and we were talking about what we wanted to name our events and re-write our descriptions, so we decided not to post yet.
I just went to the site, logged back in, it comes to a 'Whats next?' page, and 7 links down is the 'Submit an event' link, along with a description underneath it that says (in smaller print) "to the playa calendar". Click on that link, and you are free to make your entry!
My little gift to you tonight. <3 + xO
p.s. the man burns in 73 days!
2011 was such an amazing year on the playa that there was no decompression for us?!?! 4th year was the charm!! ;) p.s. Love you.