Unlike other adblock detectors, this extension does not force you to handle ad blockers in any particular way. It gives you the tools necessary to fine-tune a solution that works for you. If you want to just monitor usage, this plugin can help you with that. If you want to display a message, or disable users from viewing your articles - it can do that too. The idea behind this extension is to detect and trigger YOUR events.
This extension installs 3 plugins: System, AJAX, and Content.
On one of my live test sites, I use the change action (enable/disable) to send a Google Analytics event so i can track the effectiveness of my anti-adblock messages. You could even use it to display a thank you message for users who disabled their adblocker!
With the AJAX plugin, you can track the adblocker state within Joomla. When enabled, the AJAX plugin works with the System plugin, and can add the user to an access level when an adblocker is detected. Likewise, it removes them from that access level when the adblocker is disabled. Imagine showing your own banner ads in place of Google Adsense when an ad blocker is detected! That's just the tip of the iceburg!
It would be irresponsible to release this without a resource to help you configure it. Visit the Ad Block Reactions section of the site to get code that you can use with these plugins!