Make one. I did, and it's easy. I don't have any special talent for woodworking, and only used powertools to make it. I made my plan, bought some hardwood, cut it to size into the L shape I wanted to fit against two walls, and sanded down the edges. I then applied some dark oak stain, and secured it to the wall using corner braces.
I now have a legless 'floating' desk at the optimal height for my chair, which has plenty of space for the all the things I use a desk for. It doesn't have any drawers or shelves, it's just a simple surface, but for me it's perfect. My LL71 sits neatly under one section, as does printer, sub-woofer, and reserator in the corner, and I still have footspace in front of my screen.
Total cost: ~£18.