I would like to find out how to get a helper dog?

I was in a bad auto accident on October 31st 2008 which left me a quadriplegic. I have use of my right arm but only three fingers work on it. I'm also blind in my left eye so there goes my depth perception its kind of comical at times but no 3-D movies for me that sucks oh well. But back to the helper dog I was at the Mayo clinic the other day i'm there alot these days but i'm only 20min away so that's very nice. I seen a fellow in about the same condition and he had a helper dog he said it has changed his life and gave him more independence i'm working on gaining more independence since my accident i've barely had more than a hour alone there is all ways someone here I think helper dog would greatly benefit me.