If you've never managed a proxy before, this program might not be the best place to start -there's no help file, and it's not the most intuitive process. While you can add IP addresses and user names to the proxy, you also can block addresses as well.
FreeProxy also is able to track connections, and record them on a log file. Yet we were surprised (and a bit alarmed) to find there's no password protection or other security feature for people joining the group. Overall, FreeProxy's good for a small party, but it's not for beginners.