Five major Pirate CD makers are SM or sonmay (See Ys II Sample below), Alion, Ever Anime, Miya Records and something with a wierd symbol I am unable to make out. These are the big ones I run into more than anything. One comic shop in my area literally has dozens of game music CDs for sale all the time, but every one of them is a pirate bootleg CD. It's a shame, too, because otherwise it's a great place.
Here is what the Ever Anime logo looks like:
If you see this symbol on any CD, beware, it is a pirate: