Try A LOT of a cheapie conditioner (or any one that gives you good "slip") You may need to add some type of oil, jojoba, olive, carrot, etc to the conditioner to get better "slip".
I've used Suave Milk and Honey to detangle.
Totally saturate your hair with the conditioner, you want your hair "juicy". =)
Keep yourself calm, and be patient (so you don't end up ripping your hair out - the "hair locking" has you anxious, you just want your hair to be back "right" - but TAKE YOUR TIME)
DO SMALL SECTIONS AT A TIME, don't try to comb through a whole side of your head.
Detangle starting from your ends using a wide toothed comb ( I use a Jilbere Shower comb or a Plastic K-Cutter/long toothed pick), continuing up the length of hair to the roots. Twist or braid each section after you've detangled it to keep it "in line" =).
Relax, and take your time.
It sounds like you haven't totally detangled your hair in a while. DON'T STRESS too much about shed hair. We're supposed to normally shed up to 100 hairs daily, if you haven't detangled in a while, these will get twisted up in your hair. When you DO finally comb through, it seems like you're losing a lot of hair.
And "listen" while you're combing out. If you're hearing a lot of "snapping", "juice" your section up with more conditioner, maybe make your section smaller, and TAKE YOUR TIME. =)
You CAN get it untangled!
Hope this helps!!
) It took 3 days and 2 friends to help me detangle my hair, but I was able to do it. Just relax, relate, release. Pop in a good movie and get a really good detangling conditioner. I'd get something that softens the hair a little, like Elasta QP's Intense conditioner...or even the breakage control serum. The serum has saved my fine, easily tangled hair on many occasions, but only after I packed it on and sat under the dryer for about 20 -30 min
My hair was matting so bad that I could hear it breaking-off whenever I tried unsuccessfully to comb it. I spent so much time searching for a remedy on the LHCF board last week that I missed a whole day. 
