The author's text web site has many links of its own.
A tutorial
on using SPSS, a point-and-click statistics package available
in the Rutgers computing labs (Windows machines).
A general (java-based) statistics tool:
Correlation and scatter plots:
A correlation calculator, which includes variance and covariance statistics, and a scatter plot
A correlation guessing game, which will give you a better sense of what the various values of r really mean.
Regression:
An on-line tutorial about regression.
Try the WebStat button up above.
Data Applet, another java-based general statistics program that includes regression,/p>
An on-line calculator --no graphs, but it shows the intermediate calculations.
Probability:
Some nice normal distribution calculators.
A binomial distribution calculator.
The normal approximation to the binomial distribution.
Hypothesis Testing:
A 2 sample t-test calculator
A paired t-test calculator.
A chi-squared calculator for contingency tables.
An experimental web-based statistics textbook. Use the username "seestats" and the password "checkerboard".