I have an application written in Visual Basic. It's a search program where the user would enter six specific items in a set order and the program searches for matches in an Access database. What would it take to get that application on the Web as a feature of our company's existing Web site?
That depends. Is it a true 3-tier application? Is there business logic embedded within the VB forms?
If the answer to the first question is yes, then it is as easy as putting a Web interface on the Middleware components. If the answer to the second question is yes, then whatever logic is in the VB forms that is NOT related to the User Interface (UI), must first be pulled out into Middleware components. Those components can then be wrapped with an ASP or ASPX front end.
If you have COM+ components (DLLs), you can run them through the .NET upgrade wizard by opening the VB6 project in .NET. The wizard does a decent job of upgrading the code to .NET, but not everything is directly translatable. One example is variant data types - there is no .NET equivalent. Things like that must be upgraded manually, but the wizard will mark all of them for you when you run it.
There is a moral to this story:
<soapbox_warning> Even when creating a VB or VB.NET desktop application, always adhere to strict 3-tier design guidelines. Your application will be easier to maintain and extend, you will be able to reuse code throughout the application and you will be able to use the business logic in other applications or put another UI on the application, such as a Web front end. </soapbox_warning>