UNC Handouts on Writing - Writing the paper; Citation, style and sentence level concerns; specific writing assignments/contexts; writing for specific fields. Lots of good stuff on one page
The Purdue Online Writing Lab (OWL) - includes academic writing, grammar and punctuation, subject-specific writing, job search writing and many citation styles with examples
Research and Documentation Online (Diana Hacker) -includes sample papers in humanities, social sciences, sciences and history; also, a glossary of research terms and tips for evaluating sources
Advice on Academic Writing (University of Toronto) - good ESL writing tips and tips for writing in classes outside your major
These are web-based personal citation databases and bibliography creators that allow you to import, store, and share your research citations and automatically format your bibliographies into whatever style you need (APA, MLA, Chicago, and many more).
More information: Citation Styles