There are some contribs for that: mrtg, sysmon, phpsysinfo, geeklog, isoqlog, sarg, disk usage ibays/users, awstats and whatnot. If you want to see logged on users type "users" at prompt, no gui for that neither for running services afaik.
If you want to built a "gui" for services you could, for instance, issue ps -AHf > processes.txt
every 5 minutes via cronjob or MasterSleepy crontab-manager server panel, move processes.txt to wherever you like and/or build some html around it for viewing pleasure and open it with a browser. Similar goes for the top
command.