my friend was put on a reality show called parking wars where she never signed a waiver to air,just recently the episode premiered .what can she do?

Whether your friend has any recourse depends on the law of right to privacy, also called right to publicity. In general, people have a right to prevent their likeness from being used commercially by others without permission. However, this law varies from state to state. It's not clear which state law may apply if the episode aired around the country. Additionally, there are instances where verbal permission may be valid. Your friend should check with an attorney familiar with the right of privacy (publicity).