Hi Greg,
There is an alternative to think about. If you were to pick up an inexpensive Garmin Nuvi it will create a track file as you travel. It can then be easily downloaded into your PC for analysis later.
If you turn on the GPS when you start out in the morning and clear the old track file so a new one starts clean, here's what you can expect to get from the track file at the end of the day.
You'll get an actual visual track displayed on the map of where you have traveled during the day. Inside the track file itself are a series of data points that include a bunch of stuff, but of interest to you is that each data point is date/time stamped. It shouldn't be difficult to quickly figure the time spent at each stop from these time stamps.
You would need a Garmin program called MapSource to do the download to the PC and track analysis, but we can help you get it installed for free (yes, it's even legal). It's not terribly difficult to export the track data to a spreadsheet to do further analysis if it turns out to be useful.
As Marvin mentioned, you can get a free 60 day trial of MS
Streets&Trips. That will allow you to look at it on your PC, but without a GPS receiver for it you won't be able to get any idea of its navigation features. I've been using Garmin stuff for a long time and I'm a self-confessed Garmin bigot, but I genuinely find the navigation features of Streets&Trips to be rather a pain to use. Also, if you can't do what you want inside Streets&Trips, you cannot get any data out of it. It has no export features at all.
What I would suggest is to fire up your favorite search engine and see if anyone has created an application for the sort of things you want to do. I have to figure that someone has created that sort of thing for travelling salespeople. It almost seems a no-brainer that something like that already exists.
...ken...