Perhaps
This Link will be of some use? if you do decide to use any of the files you will need to rename the downloaded ogg file to exactly match the coresponding ov2 file as the ones I linked to are designed for use with a specific database from the same web site.
If you are trying to get them to work with the TomTom database put them in the sounds folder, if they are custom POI style cameras in normal ov2 format put the files in to the North_America or Western Europe folder as applicable - Mike
950, 940, 930, 720, One Third Edition, One XL, XL IQ Live and a dead 910 as well as PDA based software and an iFone 3G & 3GS