So, I picked up Green Lantern Rebirth...

[Patriot Mk2]

Okay, I finished it. It was good, a bit confusing though.

One question; who was the small guy in the prison with the big head? Some kind of Sinestro person?

Hector Hammond. Old school GL villain, psychic, general nutcase. Check out GL #4-6 for an arc with him, pretty good.