Integrating plugin page into WordPress

Hi

Im pretty new at WP and i hope you can help me.
Im writing a plugin which lists some items and i would like to display a page with detailed description when user clicks on the item link. Normally i would do something like
<a href="item.php?id=3">item</a>
but i dont know whats the common practice in wordpress? Especially if its using user friendly urls (like /archive/2010/…).
Im inserting the initial content via shortcode on a custom page but im at a loss what do to next.

Thank you for your answers