Even if you try to obtain them from the government source directly, they charge you a fee in order to do that. There are some cheap resources like http://is.gd/policearrest that do this in bulk and provide this for a cheaper rate so you might want to give them a go.
There are many places online to search for arrest records. You can search your local county websites to do a search or try to access public court records. Sometimes they are not accessible online and you will have to pay.
I think some government websites offer free police records search on their residents, so try finding your state's government website. You may still have to pay some processing fee though. A good idea is to run a background check on the person you want to know police records of, because background check records usually contain all comprehensive records including police arrest records. Some good information on police arrest records website is available here: http://bit.ly/Police-Arrest-Records
The fact is there's no detailed technique that gives a totally free background check search engine. The only data source sufferers may obtain for free of charge are usually local government organizations. Which are restricted by location and data type. In order to view almost all background documents. A specialty company is recommended.