delete all of the following browser extensions that you find: Searchme, Slick Savings, Amazon Shopping Assistant, Ebay Shopping Assistant, Domain Error Assistant. (See Identifications > Examine Browser Extensions for instructions on how to locate your browser extensions.) Not all of these may be present in all browsers.
Move the following items to the trash. Note that, if you don’t know how to locate a file or folder based on the paths, you should read Locating files from paths.
~/Library/LaunchAgents/com.spigot.SearchProtection.plist
~/Library/LaunchAgents/com.spigot.ApplicationManager.plist
~/Library/Application Support/Spigot/
You will also need to change the home page and search engine settings in your browser’s preferences.
Source: Adware Removal Guide : Spigot