Only just spotted this great thread as I don't tend to visit as often these days, but I'll add my thoughts in case some may find them helpful.
English Woodlands
I have the great good fortune to live only five or six miles from their yard and it is always my first, and usually last, port of call. It has changed quite a bit in the last couple of years or so and there are pluses and minuses to this. On the plus side a new broom has made the place much more efficient, user friendly and well organised. The new man has I believe injected money and this plus increased efficiency has enabled them to make significant investment in the site both in terms of buildings and equipment. The stock is now much more comprehensively sorted with exceptionally wide or fine boards and those displaying ripple in separate racks. The downside is that the exceptional boards are priced accordingly, so the chances of sorting through the stock and finding one or two great boards at a standard price are very small. If you value your time and believe top quality is worth the price, then that’s fine but some of the exceptional stuff can be very expensive indeed because London is only 50 miles away and professionals working at the very top of the market there can pay these prices and still make money. Even so, they do their own drying and do it well and you can still get excellent timber at a sensible price.
Oak
I love quarter sawn oak, including the medullary rays in all their variety but, if you making something for domestic use and have a female partner, make sure she shares your enthusiasm for them because I have heard of women disliking them on the grounds that they remind them of stretch marks and don’t want them on their furniture!
Sycamore
It baffles me that sycamore is so little used, it is one of my favourite timbers. Yes, it does need careful drying to avoid the dreaded grey stain, but I have bought it from both English Woodlands and W. L. West and never had a duff board. I am sure there must be plenty of other woodyards around the country who are doing a good job with it. It’s a little softer than American hard maple (a fairly close relative) but just as attractive and can often be had with stunning ripple. The biggest bonus is that it doesn’t have to come from the other side of the world. What’s not to like?
Hornbeam
Hornbeam is very pale and a bit bland but is very hard and dense and would make a great bench worktop. I have bought it planked from the National Trust’s estate office at Hatfield Forest in Hertfordshire. It’s not kilned but that’s not a problem if you are patient and are able to air dry it. They also have oak, ash and field maple which has very similar character to American hard maple.
Cherry
I have used American cherry quite a bit and agree that it is very reliable but, for my taste, it's aged rather orange tone is is far less attractive than the paler English cherry. It can be found but isn't really a commercially grown timber.
Other sources
Thereis no doubt that there is some fine timber felled in fields and gardens. The difficulty is getting it out. Furniture maker, Brendan Devitt Spooner, has a tree surgeon and forrester son and harvests a wide variety timbers in this way which he has sawn and then air dries from which he makes some very fine furniture - I recently saw a gorgeous table of his made from holm oak. Shame he doesn't sell his timber, but his yard is a mouth watering prospect for timber lovers!
Jim