Are you using a custom theme. ??? If so then you will have to manually edit some files in order for the package to show. All the edits for the ad management mod are stickied to the "Theme Support" board over at www.smfads.com Any other help you might need can be gotten here:
usually in a situation like this it means that the edits did not get done to the modifications.english.php file in the language directory of the theme you use. If you are using a custom theme then I suggest copying the modifications.english.php file from the language folder of the default theme to the language folder of the theme you are using. If there is not language folder than create one chmod it to 777 and copy the file in to that directory.