XForms for HTML Authors
XForms is the new markup language for forms on the Web. This document is a quick introduction to XForms for HTML Forms authors. It shows you how to convert existing forms to their XForms equivalent. It assumes knowledge of HTML Forms, so is not a beginner’s tutorial. Although there is mention of additional facilities of XForms beyond those possible in HTML Forms (marked with an asterisk on the headings), it is not a full tutorial on all features of XForms.

I think it’d be foolish if we didn’t at least read about xforms, I’ve been looking at GUI tookits lately too, like WxWidgets, XUL, XAML, TKinter and a few others- if anyone knows of any other gui toolkits preferably with a gecko widget let me know.