How do I sue someones home owners insurance for falling down the steps and breaking my leg and would I have to pay any money upfront?

You can't sue someone's insurance company, you have to sue the owner of the property, and they will notify their homeowner's insurance carrier who will defend the claim and assign a lawyer if it cannot be resolved. If you broke your leg, it is probably in your interest to hire a PI attorney.  Personal injury attorneys take  cases on a contingency basis which means you only have to pay if you succeed.  Additionally, initial consultations are free. You can use the "Find a Lawyer" service through this website to research personal injury attorneys. Then, visit each attorney's website and select a firm that has a record of successful verdicts. Click here for more information about me. Click here for more information about my firm. Please note that by attempting to answer your question, I am not acting as your attorney. I will do nothing further to protect or preserve your interests in the absence of any additional discussion with you about this matter. John Ratkowitz, Esq. Starr, Gern, Davison & Rubin, P.C. 105 Eisenhower Parkway Roseland, NJ 07068 Office: (973) 830-8441 Cell: (732) 616-6278 Fax: (973) 226-0031 Email: jratkowitz@starrgern.com  Skype: john_ratkowitz Web: www.starrgern.com.