First, I mis-types, that's IIS, not ISS..
Second, yes, GoldMine remote users have their own copy of the program with a local copy of the database. They sync periodically and update, two-ways. It's a very intricate dance, under the hood.
If they're connected to the VPN, by definition, they're on the internet with a secure connection to your network. They're part of the network, they just don't have a 10/100/1000Mbit connection, they have more like a cable/dsl speed connection. Regardless, they can see network resources like an intranet server hosting a few .asp pages that pass queries to an SQL database. It's not uncommon.
The GM+View tab in GoldMine allows one to pass data from the current contact record to a web page. Common uses are for things like passing the contact's address to mapquest or google maps, passing the current contact's zip to weather.com, etc. In your case, I assume you'll be passing a 'customer number' or some other unique identifier to your external database in order to shape a query to return some data. Common uses for these sorts of displays are to show accounting data, marketing campaign data, etc. etc.
If you find that you need assistance with this stuff, I've helped many companies design jsut such systems. It's what I do!
Doug Castell
Castell Computers
(310)601-4738