Mondivirtuali:
There are plug-ins for all the big modelling-tools to create normal-maps from highpoly-models. Most of those plug-ins are based on the ATI sdk.
Besides that there is a tool called Melody from NVidia and another ORB (Open Render Bump) from an university.

To the others:
Could someone please add the improved version to the WIKI? With that we have the old shader 2.0 version and the new one supporting shader 3.0.

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