Look at
these posts on the Sony forum, most if not all of those should work on the Ez Reader
You can see the pictures of the lights in use there but the favorites are(In no particular order):
Mighty Bright Extraflex2
Mighty Bright Duet/DoubleFlex
Verilux Full Spectrum Light
I personally use the Mighty Bright Duet(also called doubleflex), and it works great providing even lighting on the whole screen of my 505. The duet is like that kindle light but with two arms with lights instead of one