I downloaded the zip file and unzipped it onto my computer.
Where do I put the lib files so that it recognizes the imports?
Well, you must put the com and the org ackages on the classpath, so you can import then correctly, it wont work if you put them into a different directory because they are classes that have a defined package structure.
If you are building them from commandline, as I assume you are, it doesn't really matter where you put them -- only thing that matters is that you define them in your classpath when building.
For example, if your lib file is in the folder 3D/Stuff/Lib and your app is in /3D you would do:
javac -classpath .:Stuff/Lib/theLib nameOfFile.java
Hope this helps.
-Rav