Tests for motility/colon inertia

I have a long standing history of constipation and slow transit. I diagnosed myself with slow transit because the GI doctors just would not help me and kept insisting it was related to opiods or "just" constipation so I just kept using what I needed to have bowel movements by any means possible. Even to the point of staying aake all night with bowel pain. Finally I stopped having bowel movements at all no matter what I took. Even megadoses of stimulant laxatives and I finally had to say I thought I had colon inertia to have my current GI doc say "Oh I have no doubt you have slow transit constipation". Yet she gave me no suggestions. I finally found my own colo-rectal surgeon who is doing motility tests. She said she would start at the rectum and work her way up.

Since I have been reading this I have found numerous disorders I had never heard of. I am very frustrated that no one has taken me seriously. I even changed to a Dr. 70 miles away at the advice of a person on one of the message boards.

I have burning all throughout my colon. I have extreme bloating. I am having to take colon preps to have a bowel movement. I have been on soft food, low residue diet for years. Now I am on mostly full liquids - I have not lost a lot of weight but I have never been able to eat much and stay a healthy weight. I have constant pain. I have a very sharp burning pain in my lower left quadrant and muscle spasms that feel like they are trying to hold in the colon and seem to keep things from moving through. If stool gets to my rectum I can have a bowel movement. I have PFD but that seems a result of the colon problem not the cause. Maybe they are just making each other worse now.

So here is my question. Can anyone tell me all of the motility tests and things I need to do? Can anyone recommend a great doctor near Atlanta, Chattanooga TN or even Jacksonville FL (Mayo clinic is out). I am ready for surgery I guess but have to go through the tests. I don't have much of a life.

My little sister has had IBS-C most of her life and takes Zelnorm; she swears by it. I don't know if you have ever tried it but in Mexico it is OTC (unlike the US) and she only goes to one place she trusts (here) because it's by Novartis who are the name-brand guys and not the generic guys. She's really picky.
By comparison, the cliché "difference of night and day" is what she claims it to be now as opposed to before she started taking it. I of course am not a doctor but from visual experience lived through my sister I can say that it seems like zelnorm could be a possibility for relief. We both wish you well...