Just so you guys know, if you have the PC version you can farm Twinkling Titanite from the Stone knights in Oolacile when you start the DLC. As far as I know this is the only reliable place to get a ton. It's a good idea if you've stocked up some armor and weapons that require it, or plan to use Crystal Weopons the rest of the game (they can only be repaired through an upgrade).
Also the content is pretty amazing for DLC, has some nice drops, and really expands on some of the best stuff in the game (Sif & Artorias).
Just be careful about when you access it, as it is hard in comparison to most bosses in the game, and there really is no over leveling it.
After you defeat Seath, you can use the bonfire in the crystal cave to farm twinking titanites from man-eater shells. It's faster than farming stone guardians, because the shells are much closer to each other.