In Oolite, a Bounty Hunter is someone who fights space pirates for a living. GalCop awards bounties to anyone who kills pirates, so Bounty Hunting is a dangerous but profitable way to live. Bounty hunters usually prefer an Iron Ass, such as a Caduceus or a Contractor. Newly starting bounty hunters should read the wiki page, "Dealing with piracy (Oolite)"
Bounties are based on the legal status of the captured or defeated pirate, from 1 to 100 to maybe even 500 credits. Normally though, a pirate would have a 30 credit bounty. Fugitives normally have 60 to 100 credit bounties, maybe more if the fugitive is powerful and killed many traders and vipers. Be careful when attacking pirates with high bounties.
Often, Bounty Hunting is more dangerous then being a pirate and always more dangerous then being a trader. Bounty Hunters and pirates actually look for a fight, unlike traders who want to avoid a battle at all costs. Pirates can be powerful, and Bounty Hunters have to look out.
Ways to Find Pirates
Pirates often lurk in Anarchic or Feudal systems, away from frequent Viper patrols. Commanders who enter such systems are likely to be attacked, so that's where Bounty Hunters go. Bounty Hunters also stay in the space lanes, where pirates almost always stay. Bounty Hunters might also use Cloaking Devices to remain hidden from pirates until they choose to attack the pirates (bounties are not awarded if the Cloaking Device is on while making the kill).