Loading dymanic content on the same pages as the links

Hi,
How do I put a list of items in one column on the left, and each one be a link that changes the contents of the column on the right? I'm putting together some virtual catalogues and want them all to load on the same page rather than linking to a new page. I've looked up some DHTML scripts but, not sure how to use some of them as they are using code that needs to be in the section. Any suggestions?
Thanks!