These tools are useful for documenting a source's arguments, etc. immediately after reading it and keeping track of citation information in preparation for writing an annotation, citing it in your papers, and composing a bibliography.
Use this template to keep track of each source's citation and your analysis of it. To use this, download it as a .doc file or make a copy in Google Docs by signing in.
...and/or, keep track of multiple citations with Zotero software. This software saves citation information for each of your source, and stores PDF attachments, and lets you generate a bibliography from this information in any citation style. This guide covers the basics to help you get started with Zotero, including downloading it for free.