You should be looking for an experienced criminal/DUI defense attorney in your home state. I practice in Illinois, and I can tell you that in my State, third DUIs can be charged as Class 2 felonies and can carry anywhere from 3 to 7 years in the penitentiary. In our state, third DUIs are probationable though - and an experienced attorney would be absolutely required in Illinois. I am not sure of the law in your State and whether there are any mandatory sentencing conditions. It is imperative to contact a lawyer so that you are aware of your options!!
You are in need of an attorney who is experienced in your jurisdiction and is not afraid to go to trial if appropriate. There are alot of factors that go into sentencing if you are convicted and it may be wise to look at an inpatient rehab facility if your lawyer thinks that is a good idea. Regardless of the outcome of this case you need to learn more about your alcohol consumption and perhaps seek out a twelve step program to assist you.