Dynamics GP comes with hundreds of canned reports. It can be overwhelming to figure out which of the reports will really help you. Attached are some PDF files from Microsoft that show you a screen shot of each GP canned report. You might find that glancing through these PDF files is a good way to get to know the GP canned reports.
The PDF file called "Sample Reports" covers the basic GP modules (financial, a/p, a/r, bank rec, etc...).
These PDF files are specifically for GP 10 but should help anybody using Dynamics GP.