Zoterobib: Citation tool to build a bibliography in any citation style (APA, Chicago/Turabian, MLA)
Purdue's OWL (Online Writing Lab) APA Guide
Knightcite is an online citation generator service provided by the Hekman Library of Calvin College; it's free but you register to use it.
Purdue's OWL (Online Writing Lab) Chicago Guide
Society of Biblical Literature (citing sacred text)
Purdue's OWL (Online Writing Lab) MLA Guide
Chicago/Turabian formats for music (songs, recordings, compositions, etc.) (Courtright Memorial Library, Otterbein University)