Well., training as such is not requierd. It's just the approach. I also work for a smallish company but we do religiously follow test-infected-programming practise. You may start by buying a copy of O'reilly's '
Java Extreme Programming Cookbook'
Just write a small code, a login servlet/action maybe....Then write 2/3 tests to test following situations and if your action can handle them gracefully.
(1) good password, authenticated
(2) bad password -- action message or error
(3) no pass or incorrct username -- action message or error.
Just participate in Testing forum to know more.
HTH,
- Manish