I have tried the approach listed in “Getting Real” by 37signals and I have great results.
The client was very happy because he can imagine his website.
Now I am considering to buy or make such nice tools :)
http://www.uistencils.com/website-stencil-kit.html
1. Pencil
Pencil (free) is a Firefox plugin that professes to enable you to build wireframes and prototypes. As a prototyping tool it’s quite good, allowing you to quickly put together a reasonably high fidelity mockup. However, be aware you’ll still need to produce the visual design elements for Pencil, as it relies on dragging and dropping pre-made graphical elements.
The output wireframe elements that ship with Pencil do tend to be based on the look and feel of a Windows desktop application. This really is undesirable for a web application, however you could modify this with your own page elements.
Another downside of Pencil is that its export functionality provides only a few image formats. This means that Pencil falls short of being a real interactive prototype development tool.
Balsamiq Mockups
Balsamiq Mockups (price:$US79, demo available) is an interesting product running on Adobe AIR. Its representation of the interface elements has a refreshing hand-drawn, sketch-like quality to them. This does help promote the degree of changeability of the wireframes, as they look very much like a draft. If you lack the skills to create hand-drawn sketches then Balsamiq is a useful tool, as it allows you to produce quality roughs. Balsamiq also offers a standard collection of interactive screen elements, which is helpful to start off with.
http://gomockingbird.com/ is like balsamia
https://www.jumpchart.com/ – for very simple pages- I cant find how to change the layout.
Denim
A java based.
http://dub.washington.edu:2007/denim/
Eclipse based plugin – http://wireframesketcher.com/
And a nice topic in stackoverflow http://stackoverflow.com/questions/55363/best-tools-for-creating-website-wireframes
iphone
http://iphonemockup.lkmc.ch/