If you can read german I'd suggest to read the article by Markus Voelter on MDA in the July/August 2004 issue of object sprectrum magazine. It provides an overview to current issues with MDA. Download from Voelter's homepage or a short introduction to MDSD by Dave Frankel. The MDSD homepage has more resources to generative approaches. Softmetaware has a nice collection with MDA/MDSD tools e.g. OpenArchitectureWare, an open source framework for MDA/MDSD generation purposes.
Jorn Bettin, Model-Driven Software Development covers MDSD quite extensively and also mentions valuable MDSD desing patterns - the best I've read so far.
Markus Voelter, Parsen und Verarbeiten Textueller Spezifikationen, explains the differences between concrete textual syntax and the representation in an AST.
Markus Voelter/Jorn Betting, Patterns for model-driven software development. How to generate a meta-object protocol layer. How to exploit the model. How to integrate different DSLs etc. Excellent.
Jorn Bettin, Model-driven Software Development Activities.. The process view of an MDSD project
Jorn Bettin, Process Implications of Model Driven Software Development Objectspectrum Article . This article is also available in German
b+m AG, Generative Development Process. The b+m generator toolkit is now used quite frequently in the software industry.