I can't recall seeing any anywhere, but if you find any, please share with the class- I run an epic game with a fairly heavy psionics component, and would love to see some epic psionic support. I was really hoping that Complete Psionic would have some epic goodies in it, but iirc it didn't.
The Epic Level Handbook does provide rules and guidelines for developing Epic Psionic Powers, but none have been created officially by WotC. Obviously, Epic Spells could be converted to Epic Psionic Powers by, well, changing the seeds and the type (from arcane/divine to psionic). One perfect conversion would be the Epic Spell that absorbs damage and then deals it right back in return, that'd make a good Epic Psionic Power.
As for original Epic Psionic Powers, WotC has turned a near-blind eye towards psionics in general and a truly blind one towards epic material so the chances of epic psionics is, well, nigh impossible.
You can go to www.paizopublishing.com and go to the Request an Article message boards. You can also write your own article and send them a query about it. If it's accepted then pat yourself on the back for enhancing D&D even better than WotC has, heh.