Is there some type of a report I can run that shows me all the new G/L account numbers that have been added over the course of a year?

I don't think so. Could you explain why you are looking for this?

You could Excel Direct you current chart and do the same thing from a "last year end" backup which you most likely have kept. It is a fairly easy to compare the 2 XL sheets to see what has changed year over year.

GridView with the Posted Transaction file could also be used to see what accounts/departments had no postings to previous years

Just wanted to give my accountants a heads up on how many new accounts they might be dealing with. Yeah, I know I could do an Excel comparison, I was just hoping I could spit out a quick report.

There would be a number of ways to do this fairly quickly in GridView, at least get a short list of "possibilities" of Accounts/Depts that had no posting prior to the current year.