you can populate a drop down menu with the player names from your database, and add a submit button next to the drop down menu, once they click the submit button it would reload the page and pass the player name in a variable to your script so it would know what info to load.
you'd need the javascript onchange event, or you can add it directly to the drop down box by adding onlick="javascript or function goes here" try these...
http://lab.artlung.com/dropdown/
http://www.javascriptkit.com/jsref/select.shtml
http://www.faqs.org/docs/htmltut/forms/_SELECT_onChange.html
if you don't want the page to reload, then you'd need to use 'ajax' which is a combo
of html, css, javascript and using the DOM, i haven't quite wrapped my head around ajax and mysql yet though, but i have about 10 years experience with html,javascript, and php.