go online and look for your clerk of court website in your jurisdiction. then do a party name search. if you can't do it online, then go down there in person and run a search.
There may also be a limit in your Small Claims court system as to how many suits someone can file before they are considered a "vexatious litigant," so you should check Small Claims records also.
Disclaimer: Please note that this answer does not constitute legal advice, and should not be relied on, since each state has different laws, each situation is fact specific, and it is impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue. This answer does not create an attorney-client relationship.