Hello,
We also went for double glazed woden frame windows and doors, love the natural look of wood and are delighted with the product. After a bit of research, we bought from Wright Window Systems (who appear to deal nationwide, or at least they did when we bought) - good price and very good customer service.
I've no relationship whatsoever with Wrights, but delighted to recommend them, just as quickly as I'd slate a firm who gave bad service.