If you are willing to use another database, I recommend downloading mySQL (http://www.mysql.com/downloads/index.html), the myODBC driver and winMySqlAdmin server. mySQL works on stand-alone PCs, in networks and on the internet, for small, medium and large scale databases. Read their licensing agreement. It's quite liberal. All this software is FREE. the installation is easy and VB6/ADO/myODBC works cleanly. If you still want to use Access tables, WITHOUT the users having to purchase MSAccess, you can create Access97-type databases and tables from within a VB6 application using the ADO Extension for DDL and Security.
You should have no issues retrieving data from an ms access db regardless of whether or not it's installed on a given machine. Assuming you are using an external application and hitting the db via odbc or something comparable. I have written a few applications that use access db's through delphi etc.. it works fine.
I don't believe MySQL is free anymore. I tried using it for few months back and got calls from their sales people asking to buy it. After reading the license agreement on their web site, I shockingly discovered that MySQL is free ONLY if you make products that you give away for free. Anything else - licenses go from $400 and up (less for higher volumes).
I don't think people still realize this - they may have to shell out after the fact...
Nothing surprising though... lots of formerly free software is going commercial (Apache is a venerable exception! - so far...)
You only have to buy a commercial liscence for MySQL if you are selling software and do not provide the source code. You can use it freely if you don't distribute it as part of Non-GPL software.
Free use for those who never copy, modify or distribute. As long as you never distribute (internally or externally) the MySQL Software in any way, you are free to use it for powering your application, irrespective of whether your application is under GPL license or not.
Yes, and the point is, you should include the cost of any database that you use in the cost of your product. (If there is such a cost, then obviously your product is not "free" ... and that is okay!)
Otherwise, you simply stipulate that your product requires that such-and-such a database already be installed on the host computer.
Incidentally, imho, when people state that such-and-such a software package is "free," they're really being misleading. Since a person's time is never "free," the cost of supporting and maintaining it is always there. If the vendor of a product neglects to charge money for it, then the customer bears the full cost of supporting and maintaining "something he didn't write," instead of only a pro-rata share. Only a hobbyist wants to buy a "kit." You might well find that your product is more successful if you charge a reasonable sum for it and promise (and provide!) good support. Something to think about.