Easy Sermon makes adding sermons to your church website easy and painless. Now you too can have a great sermon archive
The plugin works on the assumption that there is no other page called 'sermons'. It then creates this page and adds all the content there. If you already have a page called 'sermons', then there will be a clash and the plugin won't work. The best solution is to rename your other page's title and slug. The worst solution is to hack every file in the plugin!
If you are comfortable editing theme files, Easy Sermon has a template file that it uses to display its contents: 'archive-sermons.php'. You can create this files in your active theme directory to have complete control over the way information is displayed.