One of my colleagues said that he always puts his requests in directly through the City Attorney's office. Yes, I know, lawyers, everybody's favorite, but they actually know the law. The Request for Public Information Statute requires public entities to supply the information within 30 days of the submitted request. This should work for all levels of government.
So the next time you need some government info (that's not top secret that is) go through the lawyers!
UPDATE: Albatross at Strange in San Antonio added a great comment:
If you don't get a response within 10 days from the government that tells you when you can get your documents, you can complain to the Attorney General. It's state law.
Of course, there are certain guidelines you have to follow. There's a lot more official information here.