Tina,
Short story:
I'm sure you can use the techniques taught in the book to develop web applications. Try to move most of your business logic to POJOs; use the web components for presentation and control. If you're using EJBs, move the business logic out of them into POJOs (basically making the EJBs just facades). You can test POJOs much faster and more easily than you can the components that have dependencies on the web and EJB container.
Longer story:
I'm actually trying to introduce the practice of test-driven development on the web development project I'm working on right now. We're using Struts for the presentation and control tier and EJBs for persistence and other backend services.
One of the things we've had to struggle with is the difficulty and complications of trying to test-drive web components and EJBs. The difficulty arises when we have to deal with dependencies on the web and EJB containers. There are test frameworks out there that help in these areas but since most of our developers are not very familiar with them, it's making the learning process even harder. So, to start our developers off with just plain old JUnit, we used some of the ideas in
this article and moved most of our logic out of the Struts classes and into
POJOs which we can more easily test-drive with JUnit. (The EJBs are a slightly different story though, since the code for those are generated by a tool we are using

). This strategy has the added benefit of making us refactor our code base so that we have a better design and clear separation of concerns in the different tiers.
I also introduced the concept of Dependency Injection to help loosen the coupling between our POJOs and the services that they used.
I know some of these concepts may seem like they are advanced but I have found that even the relatively inexperienced developers on my team can grasp the concepts and can appreciate the benefits of using the related techniques.
(Hopefully, I will find time to update my blog soon to give some detailed coding examples)