has anyone replaced the front wheel bearings and what are they like to do?and what sort of cost and where to go for bearings?

mine seem to be rumbling

The wheel bearings aren't very nice to do. The bearing is a hydraulic press job to remove and install, once you have the leg off. The new bearins are slightly larger on one edge and will damage if installed correctly. Also if the ABS sensor is not removed, it will get damaged. To get the ABS sensor out, it is just pushed in the front of the leg, and the wiring threaded through the leg, which has a plug up and under the wheel arch as it goes back. Getting the 4 suspension links are tricky, and youwill more then likley find a few ball joints which are starting to knock. Oh, and if the top pinch bolt isn't seized, your lucky, very lucky. VW had to make a tool to remove that bolt if, I mean when it gets seized. All in all, not nice.

Cost wise, not too sure, but worth every penny for someone else to do it.

Good luck.