Aha! This is a followup post to my report on the weaving conference in Sacramento: I have found the lost name of a booth.
Chameleon Colorworks impressed me. This vendor offers something called OPTIM, wool that's been stretched so it no longer shrinks very much when YOU wash it later. Available either as yarn or as roving (plain or dyed). (Roving is fiber half-way to being yarn; it's usually fleece that has been carded and possibly dyed, sold as a continuous but very loose strand of fibers -- usually about an inch in diameter more or less. If you buy it, you probably intend to spin it using either a wheel or a drop spingle, into a much skinnier strand of yarn, which may then be plied with other strands to make a stronger yarn. But there are really cozy-warm socks you can make by simply stuffing roving in between the stitches.)