Andrea Lunsford's Easy Writer, Fourth Edition
Pocket reference book with 2009 MLA and 2010 APA updates. Site offers overview, features, sample chapters and more.
Diana Hacker Research and Documentation Online
A guide for finding and documenting sources for MLA, APA, Chicago and CSE. Provides explanations and examples for internal citations and bibliographical entries.
Purdue Online Writing Lab (OWL)
Online writing aid that offers over 200 free resources in the areas of research, grammar, mechanics, writing, styles, ESL and professional writing careers.