You may find the following nodes helpful when learning to read/use complex data structures:

intro to references
References quick reference
Not Exactly a Hash Tutorial
Re: How can I visualize my complex data structure?
Re: I've got a hash of hashes how do i get my values out (this one is especially interesting since its output is almost exactly the syntax you'd use to access parts of your struct in a Perl program...)

This might help, too: List the Processes Running on a Computer

HTH,