Need to get help for father with dementia & doctors are syaing he is not ill, what do we do?

Dad had tumor removed behind the pituitary gland in 1999. Since the surgery he has been physically off balance, and in the past 3 years has become extremely disoriented, not recognizing his family, forgetting where he lives, getting lost, halucinating, and all these sysmptoms and many more have been becoming increasingly greater over the past 12 months. We have visted with a neurologist who says there are no signs of Alzheimer's and has sent us to a NeuroPsycholigist, who told us he had definite memory p[roblems, but then reported back to the Neuroligist that he should request a second opinion (which will take another 4 months) or send him to see a psychiatrist. We don't know how to proceed medically or legally, but this is getting worse by the minute. He does not know his wife of 38 years, and thinks she is his caregiver, and trying to take his money.

You need to find another Neurologist. Also, you might check out this website. http://www.dementia.com/home.jhtml?_requ...

My Mother had Alzheimer's. The dementia associate with it is awful! I know it is hard, hang in there!

You need to find another doctor right away. When my father started getting confused, our family doctor gave him some simple tests which showed he was impaired. Then he went for an MRI which showed brain atrophy. Those two things together point to Alzheimer's. Unfortunately the only way to know for sure is during the autopsy when the doctor makes slides of the brain and examines them. :( But he didn't have to go to any kind of specialist.
I don't believe a psychiatrist can help someone with dementia. People with dementia can't learn anymore, can't reason or be reasoned with. (Which you've probably learned the hard way.)
You might want to try to contact the Alzheimer's association-link below. There are chapters everywhere--they will probably be able to refer you to someone.
If you dad does indeed have AD there are drugs which slow it down. They don't restore anything but they're better than nothing.
You aren't alone in this. I have a whole blog about my experiences with my dad, who is stage 2/3 in AD. Write to me if you need to.

Get a different doc as many times as it takes until someone helps you. See a geriatric psychiatrist. Take a film of him acting out if he doesn't do it at the dr. office. DON'T TAKE NO FOR AN ANSWER.