If you're getting repeated text messages from a number you don't recognize, you may want to use a reverse lookup service to figure out who's sending you the texts. While a traditional phone book allows you to use the name of the person to find the number, a reverse lookup service allows you to use a person's name to find his number and address. Note that reverse lookup services cost money when you're trying to find the owner of a cell phone, as that information is not kept in the regular phone book.
Go to FreePhoneTracer.com and type in the cell phone number of the text message you received into the "Search" field. The free report tells you what city the person is located in, though you'll have to purchase the full report -- about $10 as of the time of publication -- to get the name and address of the person.
Go to Intelius.com and enter in the phone number. To access the information that Intelius.com displays, you'll need to purchase a complete report which, as of the date of publication, costs about $1.
Visit CellPhoneRegistry.com and input the number that's been texting you. This service usually provides a name, address and any available public records. To access this information, you'll need to pay around $15 for a full report.
If you're receiving harassing text messages, you can file a police report and they can trace the number for you.