we use Bluepoint (www.bluepoint.net) for our supplies, very hard to beat on prices - USB A to B cable 0.10p !!! 17" TFT £112 , mice from 0.72 pence.
You will have to get a login to see there prices, either buy creating an account or by logging in as guest, they change the password every day for that. Call them 0870 121 8001.