You are NOT required to choose one of the lawyers who sent you a letter or a brochure. There are many good lawyers who generally don't send such letters. If you don't know any lawyers, you can ask friends, relatives, neighbors or co-workers for recommendations. You can look on-line or in the phone book. You can consult the State Bar of Wisconsin.
Schedule interviews with several lawyers before you make your decision. Bring a list of questions and take notes. You can ask questions about your claim, the lawyer's experience with similar claims, where the lawyer went to law school and where the lawyer has worked. Ask the lawyer to explain what he or she would do to help you. If you like, ask for references from past clients. Look around the office--does it make you feel comfortable? Pay attention to the lawyer's personality--do you think you could work well with this lawyer and his/her staff? Is this lawyer tough enough or understanding enough for you? Note what impresses you favorably or unfavorably during the interview. At the end of the interview, you do not need to sign anything. Explain you are researching how you will proceed with the claim and you'll get back to the lawyer with your decision. Then thank the lawyer for spending time with you.
After you have completed your interviews, compare your notes about the lawyers' backgrounds, legal experience, claim results and personality as well as any comments from recommendations that you received. This way you can make an informed decision and pick the right lawyer!