How I can load a VRML node into Java3D? Where can I find a VRML Loader and how do I use it?

You have a couple options. First, I would suggest that you visit the "J3D File Loader Archives" at:
www.j3d.org/utilities/loaders.html

The Xj3D Loader from Web3D.org will likely meet your needs. Link to it from the archive (above), or directly at:
www.hypermultimedia.com/Xj3D

Xj3D source is at:
www.web3d.org/TaskGroups/x3d/sun/cvs.html

You might also check out the NCSA's "Portfolio", as it includes a VRML (.wrl file) Java 3D Loader. It is available from the archive, or directly from:
www.ncsa.uiuc.edu/~srp/Java3D/portfolio

Each of these loaders is well documented, so once you have a copy you shouldn't have any problems using them.