CMS System Needed Tweaking ASAP

We have a current system in place that lets users signup for a membership (sports club) and pay membership fees. Currently the admin can see all the members. All we need doing is an option for us to have user roles like a team captain to login and be able to view only his team (The people that have signed up for the team). We also want our invoice php system to collect information from the same database table as the membership system so we can invoice the same users instead of registering twice. We need this asap so give us a shout!