Stephen,
In Chapter 6 of the MM .NET Developer's Guide, there is a "Web Forms FAQ" titled "How do I dynamically add controls to a Web Form" that answers this question.
Regards,
Kevin McNeish
Eight-Time .NET MVP
VFP and iOS Author, Speaker & Trainer
Oak Leaf Enterprises, Inc.
Chief Architect, MM Framework
http://www.oakleafsd.com