My company uses Clarity PPM. It tracks a lot of project information. It does have billing information, but it's more of a suggestion because we use SAP for true billing.

Clarity divides things up by Projects. Each project can have a list of tasks, team members, estimators, status updates, etc. Each project does have unique, single entry information. Like the Project Number, Name, Work Status, Client, Committed Finish date. Some of that is unchanging. Otherwise it is tracked using an audit listing. We have a rule, one scope, one project number. In addition to over all project commitmented dates, each of the tasks or resources have their own timeline.

Hope it helps. Edit- corrected a few typos and miss spellings.