Sounds like one of two things (or a combonation of both). Either you don't have the infocenter's files in the appropriate place, or you don't have your eq2.ini file modified as needed.
Are you using a custom UI, or is the infocenter the only mod you are using? If you are, the contents of the Infocenter's download/.zip file should be extracted into the custom UI folder you have (which should put two .xml files into the custom UI's folder in addition to a 'infocenter' subfolder within that same UI folder). This
should resolve the issue.
If you're
not using a custom UI, you should create a custom UI folder in your base Everquest2/UI directory and extract the contents of the Infocenter's download/.zip file to that folder. Then you will need to modify your eq2.ini file (found in the base Everquest2 directory). Instructions on how to do so can be found
here.