- The Hitchhiker's Guide to Calculus - Spivak is a well-known author of a current calculus text. This is his overview of the field, a speedy introduction to the concepts.
- Calculus, 4th Edition - Spivak's latest textbook on the topic.
- Schaum's Outline of Calculus, 6th Edition - an outline of the topic with tons of completely worked example problems.
- Calculus: Early Transcendentals Plus NEW MyMathLab with Pearson eText -- Access Card Package (2nd Edition) - what appears to me to be the textbook at OSU for this fall.
- Paul's Online Math Notes - this set of notes over a course of calculus is recommended on math.stackexchange.com.
- Khan Academy - this is the online material on differential calculus at Khan Academy.
- Calculus: Basic Concepts for High School - a textbook written in Russia, covering the basic concepts of limits and integrals at an accessible level (if a bit quaint).