This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
Reflection only works on existing objects (and hence, classes). But you can construct classes from source code at runtime using a library like Javassist. This article I wrote for the JavaRanch Journal explains how it's done.