Any one knows where to get TR for retouch in los angels, santa monica area? And if my hair is falling out from the last TR, it was 3 months ago, is the new TR going to be applied only to the new hair or the treated hair as well?

Try checking the Yellow Pages under "Hair Salons". I'm sure there are some salons out there that offers relaxer services. If your hair is already relaxed, it doesn't need to be relaxed again. The relaxer should only be applied to the new growth area alone.