Indexed output order

Here’s a link to the output page I’m trying to change the indexed order on.
http://www.reisnetwork.com/membership/members/

Well… I’m kind of embarrassed to say I don’t know. I took over this site from someone else and I’m still trying to figure out how Form Manager does this. I simply enter the data and it shows up on the site page.
Do you have any suggestions as to where I should look for what generates the output. I’m thinking a php file in the plugin directory. I could look through those.