You need to find an employment lawyer in your area and get advice as to your rights as an employee. If there are others who are above your boss, you may also want to consider taking your concerns to them because his actions may very well be a concern for the company itself. If you don't know how to find an employment lawyer, contact the WI state bar association and they should be able to direct to you attorneys who handle employment matters in your area.
As brutal as the economy is you may have to move on unless you can go over this bosses head and that could cost you've job also. Tough situation but keep all of your options open.
You will need to provide the employment attorney you talk to more details as to what you mean by "hostile." Discriminatory actions? Sexually hostile environment? Also, have you complained to HR in writing? Lastly, if you quit, you will likely not receive unemployment benefits unless you can prove a constructive discharge.
Michael G. Miner
Midwest Legal Partners, LLC
200 South Executive Drive, Suite 101
Brookfield, WI 53005
Office Phone: 262-780-1461
Cell Phone: 248-462-5680