I read both books mentioned, which are great.
I really like the Zurb Foundation. I created several sites with it and had no problems. I found it easy to expand - it's easy to create a prototype, which will then be fully released. (I use version 2 - there is V3, but V3 refused IE7 support)
The new tool someone in the office was playing with was jetstrap.com
Allow you to visually execute flexible layouts - you can check the code and see how to do it and can be a good way to get started.
Jules matthews
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