How do I get my ex-employer from giving me BAD references?

I did not get fired, I quit and gave proper notice. I frankly had enough of my managers behavior and needed to get out of that environment. I have learned that in Michigan, its legal to give negative references as long as there is documentation to back up thier claims. I worked their for 4 years, was promoted twice and I cannot simply not put this company in my resume. The last year I worked there was horrible beyond comprehension. I kept getting write ups and I couldn't figure out what I was doing and what I needed to change my behavior. I felt that it was a contructive discharge but I never could figure out a way to prove it. I went on alot of interviews and a couple of places said after the interview that I was hired as long as nothing came up in my refrence check, Apparently something did come up-the place were I work now was kind enought to show me. It's not a very good job but, I figure If I stick it out for a year I will get something better.