Pathfind,
Have you looked into any of these yet?
I don’t have any personal experience with these programs but they seem like something I would use if the need arises.
They all offer trial software downloads and pricing doesn’t seem outrageous.

WinTac Pro: http://www.wintacpro.com/
Full software system for scheduling, dispatching, job costing, estimating, AP/AR, etc.

Qxpress: http://www.qxpress.com/
Scheduling software designed to work with QuickBooks.

ACOWIN: http://www.acowin.com/
Service and project management software with mapping, also designed to work with QuickBooks.