When starting OneNote 2007 beta you will get a warning that informs you that OneNote 2007 requires Windows Desktop Search to fully support Instant Search and Searchable images and audio. This warning will pop up until you install the Windows Desktop Search 3.0 or until you edit the registry, which then will inform OneNote to use Slow Search.
Here is how to modify the registryCreate a new text file called onenoteindex.reg and copy and paste below this text into it. Then double click the file and answer yes to the question.
Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\OneNote\Options\Other]“EnableWDSIndexing” = dword:00000000"ShowWDSUpdateWarning" = dword:00000000