Well, how about right here, the Cattle Drive? You write code assignments, you send them in to be "nitpicked", you get feedback on what you wrote, then you tweek the code some more and the cycle continues - at the end you have a really good understanding of what you're learning.
There are others of course, but, well, they can't compare with the unique experience that you get from doing the Cattle Drive assignments, with someone looking over your code and giving you feedback until it's more than just code that works.
If the Cattle Drive isn't your choice, or if you're looking for additional resources while doing the Cattle Drive, dickbaldwin.com has some tutorials on advanced java topics.
I’ve looked at a lot of different solutions, and in my humble opinion Aspose is the way to go. Here’s the link: http://aspose.com