Where do you buy your Glucosamine tablets etc?  Is there a website where you can buy any supplements at a reasonable price?

Not sure about websites but you can get them anywhere like Tesco, Holland and Barret etc
There's a website called Hyperdrug (canine chemist) maybe they do offers?

I was recommended ZipVit and have used them for some years. http://wwwzipvit.com/.

http://www.vitaminsdirect.co.uk I use the human version of Glucosamine & Chondroitin not their pet version.

I think Healthspan is very good http://www.healthspan.co.uk and very reasonably priced.  Delivery to the UK is free as well.

I get them from Healthspan too (human variety for the dogs).... they seem very cheap, and delivery is free and quick :-)