Gowebmkt,

You could use Google Analytics and track using virtual page views. This requires that you have an account with Google, install the tracking code at least on the page that you are tracking (whole site would be better), and that you add a line of JavaScript code to the link where the button is. Another solution is to use event tracking as virtual page views may skew your page view metric however if you don’t use Analytics for any other data but tracking clicks on that button it won’t really matter.

Here is a video on how to implement,

24. Event Tracking and Virtual Pageviews | Google Analytics IQ Lessons - YouTube
Hope that helps,

Shawn

If it was me Id do it with JQUERY and PHP

add to image--
onclick="$.post("trackclick.php");"

PHP file: trackclick.php
<?php

$File = "clickcount.txt"; $fh = fopen($File, 'r'); $Clicks = fread($fh, filesize($File)); fclose($fh);

$Clicks=$Clicks+1;

$File = "clickcount.txt"; $fh = fopen($File, 'w') or die("can't open file"); fwrite($fh, $Clicks);
fclose($fh);
?>

Here's an excellent article on using google analytics event tracking:
Idiot's Guide to Event Tracking | .eduGuru
This is the way to go!