Elucence is one of the best for detangling. Just ordered myself another two bottles.

Another great one is Tigi Moisture Maniac.
When you detangle, do you let the conditioner sit on your hair, or do you attempt to comb it right away? It's best to let it sit for atleast 5 minutes, preferably longer. When I CO during the week, I'll apply Elucence almost as soon as I get in the shower, handle my other business (

), and then detangle. The steam from the shower seems to help loosen tangles.
Also, before applying the condish, I run water over my hair and lightly detangle. Just enough to loosen some of the tangles, so that when I really detangle, I have an easier time.
If this doesn't help, could it be possible that you are in need of a good trim?