Thanks for that, but after a bit more tweaking (and a look at an old post at macosxhints.com) I figured it out.
1) Start Automator
2) Under "Library" click on "Finder"
3) Under "Action" drag "Get Specified Servers" to the workflow
4) Click the + (add) and select your workgroup name
5) In the dropdown list for "Show" select "File Servers"
6) In the middle column, select the server (the other computer that you want to connect to)
7) Down in the field for Address, just add a slash (/) and the name of the shared folder to the end of the address already shown.
This works for me at least for connecting to a Windows 2000 shared drive. You can then save this workflow and (I suspect -- I haven't had time to try this yet) add it to your user login options so it runs every time you boot the computer.