Yes, the top link Titles Webcontrols contains a link to the downloading of the source, which contains the sample website.
You are correct, that the samples do declare the controls in markup. The sample I pointed to shows you how to use the control in a template, which deals with the problem of the control not existing during a callback. This is what the CallBackType property allows you to do, sync a late rendered control.
In your case however, I think all your missing is the assignment of an ID for your control.