More fully functional software programs such as EndNote, Mendeley and Zotero can be downloaded to your desktop and you can save, group and search your references for re-use again and again. This can be a time-saving option if you find you will be using the same resources for multiple projects or for multiple courses.
EndNote is a software program to manage bibliographic citations, for both Windows and Macintosh. Features allow you to transfer references from databases into EndNote and then create bibliographies in a variety of formats. Registration is free with up to 100MB of storage.
Mendeley Desktop organizes your research paper collection and citations. It automatically extracts references from documents and generates bibliographies. Mendeley Web lets you access your research paper library from anywhere, share documents in closed groups, and collaborate on research projects online. Integrates with word processing software. It is a free software.
Zotero has a desktop software package as well as web-access, but also has an amazing plug-in for Firefox. Easily save citations from library databases or the web by clicking on an icon in the address bar of your browser. Cite while you write capability with Microsoft Word (additional download).
Google Scholar can help you copy/paste a ready-made APA citation for nearly any published book or article. Click on the " mark to generate citations in APA and other styles. Be aware that auto-generated citation like these often contain errors, and must be carefully proofread.
Citing something more unusual, like a blog, video or interview? The Online Writing Lab from Purdue University has produced an APA Formatting and Style Guide which provides examples of how to cite nearly everything in APA.