Before beginning the evaluation of the data, you should have an understanding of the manipulation you would like to perform with your data.  There are a number of on-line resources which can be accessed to assist in gaining more understanding and information of Evaluation and process of Statistics.

These resources are:

The Research Methods Knowledge Base by Professor William Trochim, Cornell University.  This document is a comprehensive web-based book which outlines the topics  of the research process, research design, and data analysis.

VassarStats:  Web Site for Statistical Computations.  This site explains the function of each statistical operations and allows the user to run several of the functions on-line.

GraphPad  This site provides information and instruction on performing data analysis on nonlinear regressions and