Hi there,
You've pretty much covered most of the options already, but I was going to mention the local discounter type places, and Ebay.
Local Discounters - usually found in most large towns and cities, often advertise in the local paper as well. Pro's are that you can pop around to see them and have a look at the goods etc etc. Con's are limited choice and range as as soon as they're out of a range, they can't guarantee it'll come in again as they'll be buying from wholesalers or end of line discounted items etc.
Ebay - lots of choice here and plenty of bargains. Sometimes, you'll be astounded at what you can pick up, but usually you need to know quite a bit about the product and also to compare on the exact same thing as what you may find in Furniture village or John Lewis etc. For instance, about 18 months or so ago we had the need for a full kit out of furnishings etc. The bed was one end of line, in one of the big chains at like £1800 full retail (Super King size) and was obtained off ebay, delivered for around £550. Sofa, was around £699 from Argos I think and was delivered for £279. Cons are you often can't 'see' the goods - however some furniture Ebay sellers do have premises, so lookout for those guys.
hope this helps, Cheers, DtM! West London & Slough UK!