Checking the status of a lawsuit is only possible if you have access to some basic information about the names of the parties and where the lawsuit was filed. Depending on the nature of the case, it might have been filed in state or federal court, and each of those court systems has several divisions where the case could be pending. Gathering as much information as possible about the lawsuit first will make it easier to track down whether the case has been decided and, if it has, to find out who won.
Find the name of at least one party in the case. Lawsuits are titled with the names of both parties, such as John Jones v. Sarah Smith. The clerk of court will need at least one of those names to search for the lawsuit. It is also helpful to know whether the party you identify is the party suing (the plaintiff) or the party being sued (the defendant).
Narrow down the possible location of the lawsuit. Cases are most often filed in the state where the plaintiff resides, so start there. If that doesn't work, try the state where the defendant resides. If it is a business lawsuit, try the location where either company is incorporated or the location of its headquarters.
Perform a general search on the Internet using those names and locations as search terms. This will show any news reports on the case and may reveal the specific court where the case was filed. Call the clerk of court for that court and provide the information you have found. Provided the case has not been sealed and the record is public, the clerk will either provide the result or instructions on how to obtain a copy of the judgment.
If Step 3 did not result in enough specific information, check the websites for the court systems in the states on your possibilities list. Many court systems have web-based dockets that can be searched by the name of either party. There are also web-based services such as PACER, CourtLink, Court Express and WestDockets that will perform searches across multiple states and courts, though most require that you purchase a membership.