Hello,
PeopleSoft 8 is web-based; therefore, Configuration Manager is not used to configure end-user workstations. All you need is a supported Web-browser.
Configuration Manager only needs to be used if the user is going to use PeopleSoft's Win32 executables like PeopleTools (PSTOOLS.EXE) or Application Designer (PSIDE.EXE).
Generally, Configuration Manager, for all PeopleSoft releases, was never installed on each workstation. You do not want users to be able to change their configurations and then create a non-ending workstation support issue.
If you are looking for the Configuration Manager, you need to know where PeopleSoft was installed (called the PS_HOME directory) and look in PS_HOME\BIN\CLIENT\WINX86 for the executable PSCFG.EXE. This is the standard process for configuring a workstation for technical developers or functional users that do not want to use the web-based Query Designer or Tree Manager.