Processing IVR entered data

I’ve got an IVR set up in freepbx 2.2.3/asterisk that works nice and want to add an option so that people can use their phone to enter data and that data is then passed into a URL as a parameter for downstream processing. EG enter your account number so redirected call cal bring up customer details in CMS.

I thought of using the ‘i’ function and a custom macro but that started to look complicated. Has anyone done such a thing that could help me with an example or point me to a post.

I tried various searches but couldn’t find anything along this line.