There are dozens if not hundreds. A lower cost option for a full PSA I recently evauated is BigTime. It tracks people-resources and expenses across projects well and seems to have a good connector to Quickbooks. I have not personally used it. 

It is very simple but you can't beat Harvest for tracking time and expenses across projects. It has a very simple interface to connect to quickbooks, you generate invoices in Harvest based on time 

Let's be clear: no general ledger software does an amazing job of project accounting, and of them all, Quickbooks is probably the worst of them. Sorry guys but it's true. 

For a small accounting practice the Xero practice manager system isn't bad but then... you'd be on Xero :)