We produce an application that monitors a local database for changes,
then uploads the information to a website for our customer. Our
customers would like also to upload their MS Word documents to the
website so we have suggested that we incorporate PDF functionality
into our application to convert the Word docs to PDF then we can
upload them with the data. We would like to linearized / optimise the
PDF for the web too if possible. The product we require will be either
a visual basic 6 or vb.net component.

We have one developer working on the project and about 200 customers
with 1- 5 installations at each customers location. My Question is
which product would suit our needs and how much would it cost me for
purchase of the component and are there any royalty/client costs? Our
application works without any human interaction.

Dear totaliq,

The best product for your needs is TX Text Control .NET, a
royalty-free library that supports Visual Basic .NET. Once your
developer has compiled TX Text Control .NET into your remote
application, any number of clients can run it free of charge.

To read Word documents and output PDF documents, you will need to buy
the Professional or Enterprise version of TX Text Control. The
Professional version, which is all your developer needs, costs $949.

TX Text Control: .NET
http://www.textcontrol.com/products/dotnet/

Regards,

leapinglizard

Yes TX Control can convert word documents but unfortunately it doesn't
preserve the format of the word doc.

This is a pseudo-problem. The customers only need to import their Word
dox into Open Office and export them as PDF files.

Use iTextSharp. Its opensource. 
Go to google and search for it