where can I find the best and most current versions of Microsoft's Word and Excel applic'ns for my MacBook Pro

Buy it from Microsoft (or any retailer), then update it to the the latest version.

Or if you don't feel like paying Microsoft through the nose, you can get LibreOffice for free.

I also use Open Office on my mac. And also free.

I started out using OpenOffice but I have found LibreOffice to be much better.