Simple PHP/MySQL category structure

I need a simple category structure, based on two database tables. First table is the categories, second table is the items them self. Table: Categories id parent_id category_name Table: files id category_id name dateinfo description Your job is to make a PHP / HTML page with a menu for categories on the left hand side, and the listing on the right. (See attached image) When selecting a category item on the left hand menu, the page reloads with a PHP GET variable. (ie: [login to view URL]). Thus revealing the corresponding items from the items table, with category_id tagged as 4. It must be possible to implement/include this code on an already existing webpage, through <? php include(''); ... See attached image for details on the look of the HTML page. It's not nessecary to use a lot of time on the LOOKS of the HTML page, since I will redesign most of it. Just make it plain and simple. Please let me know if you have any questions. Best regards