Police often will obtain an arrest warrant signed by a judge to apprehend a person.
Arrest warrants are used in various circumstances, such as when officers have investigated a crime, identified a suspect and then want to go and arrest the person, such as at the person's home.
To obtain an arrest warrant, a police officer usually goes to a prosecutor who then must convince a judge that a crime has occurred and there is probable cause that the accused was responsible for the crime. The judge then must sign the arrest warrant.
An arrest warrant will list the defendant's name, a narrative description of the crime, the amount of bail and the court in which the warrant was issued.
Arrest warrants generally aren't made publicly available by police agencies.
But see the San Diego County Sheriff's Office warrants database, which has summary information on warrants issued against people in that county.