An ad this week in the alternative newspaper The Alibi asks "people who hang out with crooks" to do part-time work for the police.
It reads in part: "Make some extra cash! Drug use and criminal record OK."
Capt. Joe Hudson says police received more than 30 responses in two days. He says one tip was a "big one" but wouldn't elaborate.
An informant whose tip helps officers arrest a drug dealer could earn $50. A tip about a murder suspect could bring up to $700.
It's not the first time department has run ads. In a program 10 years ago, police received so many calls they turned the phones off.