The documentation that comes with Ant sufficed for me as long as I had a sample build file or two to read. I'm not sure where a good place would be to find a simple one. If, however, you prefer a book, there are now a few books that cover Ant. If at amazon.com you do a book search for the words "ant java" (without the quotes), you'll find four matches. Good luck, Craig
I first learned Ant from looking at a few build files (check out the projects at http://jakarta.apache.org , many of them have Ant build scripts. However, I found that the book "Java Tools for Extreme Programming" (reviewed in the Bunkhouse, here) really helped round out my knowledge, especially as it adds other topics such as tools for automatic testing into the mix.