Meeting people at parties often leaves you wondering how to find the person you met again. You might not even know his last name. You don't need to hire an expensive private investigator. Use a combination of offline and online social networks to find the person without invading his privacy. If you want to contact a woman you knew in school you'll have to know how to locate someone without knowing her last name. She might not be using her maiden name any longer.
Utilise social networking sites. MySpace and Facebook give you several ways to find people without knowing a last name. Once you find the person, you can contact him through the site and exchange phone numbers or plan a meeting. Log in to your MySpace account and click on the "Friends" tab. Go to "Browse People." Type in any concrete knowledge you have about the person. Select his gender and general age range. Use the "Postcode" drop-down menu to narrow the search area within a few miles of where you think he lives. Input your postcode and press "Update." The "Advanced" tab lets you enter the person's ethnicity, body type, education, income level and height. This will work only if the person has filled out a detailed profile with all of this information. Start out with a general search and narrow it down so you don't inadvertently miss the profile you are looking for.
Use his screen name. In the Internet age your friend may have chosen not to share his last name for security reasons. He might use the same user name across several sites. This is especially handy if you meet someone in a chat room or online site. This way you'll be able to use a social networking site to add him as a friend or send a message. If he has a unique avatar, keep your eyes peeled for it while looking through local forums. He may be using a different screen name but using the same picture on several sites.
Pull out old class photos. You may only be able to remember your acquaintance by her face. If you are looking for someone with whom you attended school leaf through old photos. You'll be able to find her maiden name. Check out online reunion or classmate sites once you've found this information. The users are generally required to put in their maiden and married names, so you can find her without knowing her current last name.
Post your story. You might not be able to find a person without knowing her last name. Put your friends, family and the entire Internet to work for you. Post the circumstances of your meeting in local newspapers, on "missed connection" boards and on your blog. Give general characteristics of the person you are looking for. Hold back one piece of obvious information so the person can identify herself, such as the colour of the scarf she was wearing when the meeting took place. Avoid posting so much information that it becomes a safety risk. She may be reluctant to come forward if you share too much personal information about her. Even if you don't find the person you are looking for, you may find someone who will lead you in the right direction.