This week's book giveaway is in the Other Open Source APIs forum. We're giving away four copies of Storm Applied and have Sean Allen, Peter Pathirana & Matthew Jankowski on-line! See this thread for details.
There are quite a few good profiling tools available commercially. I suggest taking a look at the Optimizeit and JProbe. If you are looking for a free tool than take a look at Jack Shirazi's list. In general, I don't think I have come across a free profiling tool that does even half of what most commercial tools do. If you have identified a need for a profiler then I suggest invest in a tool like Optimizeit or JProbe.