Here you will find a number of online calculators for the computation of different effect sizes and an interpretation table on this page.
Statistical significance is the least interesting thing about the results. You should describe the results in terms of measures of magnitude – not just, does a treatment affect people, but how much does it affect them.
University of Nottingham: What do my results mean Effect size is not the same as statistical significance (6:46)
CrashCourse: Degrees of Freedom and Effect Sizes (13:29)
Online Statistics Education: An Interactive Multimedia Course of Study