First, make sure you have the latest driver from Epson's website; you should delete the driver you have now through Apple Menu>System Preferences>Print & Fax; then re-add a new driver.
Also, make sure your usb cable is connected directly to the computer, or a powered hub; my own Epsons don't work correctly from a lower-powered usb port such as those on the keyboard.
Make sure no small scraps of paper are stuck in the paper path.
One time I managed to get a stubborn printer working with Printer Setup Repair available from
http://www.fixamacsoftware.com/software/index.html
I used it in demo mode to fix the printer.
Well, those are the things I know from fixing my own Epsons, of which I've owned too many. That's a nice printer you have, so I hope you can get it working.
If none of those suggestions work, maybe one of the experts here will have some other ideas.
