I'm presuming you've found an answer to this by now? Anyway, you don't say how your dentist is going to treat you? There are a couple of ways, the latest being laser but I'm sure that's somewhere in the region of �600. The price you give suggests the mouth trays with gel method. My dentist charges �345 for this (as of 2006) and I'm pleased with every penny! You have plastic trays moulded to fit your mouth a bit like boxers' gum shields. You squeeze a small amount of the clear gel into the trays and sit with them on for at least 3 hours. (Best to sleep in them) You do this for approx a week and try to avoid the teeth staining foods and drinks in that time. At the end of a week to 10 days you'll have a fab gleaming smile. The trays are yours to keep obviously and you can buy top up tubes of the gel from the dentist. I sleep in mine for 2 nights every 4 months or so just to top up my white smile. (The only downside is increased sensitivity, which apparently occurs whichever method is used. The dentists' advice for that was to put a sensitive toothpaste in the trays and sit with that on the teeth for a while.)