Hall's new edition of Radiobiology for the Radiologist (6th edition) just came out.
As for rad onc texts, there's the Perez textook (last published in 2003) and the new Leibel (which was published in 2004, I think?) Unfortunately, some sections that are really good in one book are kind of skimpy in another. In general, Perez seems to be a little more encyclopedic/thorough than Leibel.
Another great resource (if you can get a copy) is the ASTRO disk that comes out each year at the annual meeting. It has "up to date" talks on most topics from people who are generally considered to be experts in their respective fields.