A good online retailer for the UK is overclockers
so I've heard. I'm ordering my computer components from there in a couple of weeks time.
In terms of monitors you might want to look at the "Samsung SyncMaster 172X 17" TFT Monitor". They have it at overclockers
, but the last time I checked it was out of stock. I'm not sure on the full specifications but it has a very fast response time of 12ms. The downside is the price, I think its around £405 INC. VAT. Samsung do a 19" TFT for £420 INC. VAT but it has a slower response time, which is also for sale at overclockers
I'll see if I can find some reviews for you.