Old Dog learning new Tricks

Thank you for the opportunity to be part of this forum.
I am an International Sales Manager, I consider myself an intermediate excel user, which learn through self lessons and using the web for cosnultations.

Now, I need to get more advance on things like what if analysis, and data caomparisson, so anything anyone has on these subjects is welcome.

Thank you and I hope I can contribute as well as benefiting from the information shared here,