Ya'll seem to like the felt rocks; I encourage you to make your own. Here's how:
Find up to 10 smallish, roundish rocks. I wouldn't go any bigger than about 2 inch diameter.
Rinse if needed (it also helps the wool stick if the rocks are wet)
Now, if you have wool roving, this will be easier and your finished product will be smoother. In Sacramento you can get wool roving inexpensively and in every shade at Rumplestiltskin. (www.yarnyarnyarn.com). I have found that the more natural colors (less bleach used in processing) felt better.
Anyway, grab a largish handful (about a 2 foot long strand) of roving and spread apart the fibers a bit and wrap around the stone changing directions as much as possible so the strands don't all line up. Don't worry, doesn't need to be perfect.
If you happen to have raw wool that you can't be bothered to card, you can use that too. Lump handfuls of it around the stone and secure in place by wrapping with 100% wool yarn.
For either method, make sure your rock is completely covered as evenly as possible (you want the rocks in your washing machine to be padded!)
Now cut the leg off a pair of nylons.
Grab a wool covered stone in your hand and shove your fist all the way to the toe of the stocking. Be sure to use your hand to keep the wool from moving around. Bad photo, sorry.
Now tie a knot in the stocking. Don't use a bit of string to separate the stones, definitely knot the nylons. Trust me ;) Continue adding stones and knots until you run out of stocking. I found 10 smallish stones was the most it could handle.
Now, be brave and put it in the washing machine. I put it in with blankets and sheets and towels (wrapped in a blanket) to protect my new front loader as much as possible. Wash with soap on hot. Regular cycle.
After the wash, the wool will have shrunk around the stones and should be all felted. It may have fuzzed through the nylon a bit. It's okay (kinda unavoidable).
Untie the nylons (you can use them again for felting) and peel out the stones.
All done! The white ones look cocoons. This one is made with wool roving:
These two are from the raw wool. Much lumpier and they didn't felt as tight. Mr. H said they looked like granite. I think they look like sheep.
That's all there is to it. Enjoy!