
Lucy - I have got the ergon grips (without bar ends), have been using them for nearly a year now and they make a huge difference in reducing sore hands as they spread the surface area across your whole palm - I'm not sure if they would help your wrists or not though.
If you can wait, the suppliers were at SSMM last year and at the London Bike Show (where they recognised me!) The ergon guys are incredibly helpful and I would suggest that you talk your sore wrists through with them.
Have you tried spacers, riser bars, twisting the bars etc? You may find that by making your reach shorter you elivate the strain on your wrists.