[notaPINKtruck]

R^2 correlation coefficients are certainly a good start for any statistical analysis of a dataset. However, keep in mind that there are many other approaches to calculating correlation than the Pearson method (a.k.a. R^2 values).

If you're really serious about it, I would suggest picking up a book on basic statistics. While you might not understand all of the underlying theory and mathematics behind some of the tests (I certainly don't), at the very least it will give you a basic understanding of them and (because statistics is, after all, math) formulas for each test that can easily be integrated into any piece of software (be it Excel or your own creation).

All that being said, ALWAYS REMEMBER: CORRELATION DOES NOT IMPLY CAUSATION. No number alone can ever give you any useful information about a link between two variables. To be useful, it has to be coupled with an understanding of the mechanics of the situation and a healthy dose of common sense.

Happy number crunching!