From September 1st, Jet Reports Express is LIVE. It has been announced before that Microsoft was working on a collaboration with Jet Reports to provide a tool that enables you to create powerful reports using Microsoft Dynamics NAV data from within the familiar environment of Microsoft Excel.
There is lots to find on partnersource:
Getting started material:
Get Busy & Good luck!
There is even a demo script to create a Jet Reports express report ad hoc.. :
Much more useful info here: