FWIW - I had the same delima when I started working with complex data structures. Not that merlyn needs any more compliments :), but I found this article of his to be very helpful in decyphering refrences.

The basic jist is that by using @{$foo->{'bar'}}, you're derefrencing the value of 'bar' as a list.. and you can work with it as a list because the corresponding value of 'bar' is a refrence to a list; not a list in and of itself.

Hope this helps..
Rich