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.
"JUnit Recipes" does briefly cover running JUnit tests with Ant, and it includes a handful of example Ant targets that come in handy in various situations.
"Pragmatic Unit Testing" is not the cookbook that "JUnit Recipes" is. Instead, it includes sound advice on how to think about unit testing. I recommend reading it, especially if unit testing a new practice for you.
Getting comfortable using Ant isn't difficult. If you've a question about using it - like, "How do I run all my JUnit tests with Ant?" - I'd recommend moseying on over to the "Ant and Other Build Tools" forum, and asking away.