Where can I find the general rules for grading around a house?

Assuming it's a slab on grade (which means the slab sits right on the ground -- it would be a pier and beam if there was a crawl space underneath), the general rule is to have at least 4 inches of concrete showing between the dirt and the brick ledge (6 inches if VA or FHA financing), then slope the ground away from the slab in all 4 directions. No general rule on slope, except that it should not be so steep as to allow soil to wash away in rain (usually 1 foot drop for 3 feet horizontal run is the limit, but it varies according to soil) and it must fall away in such a way as to protect the slab from flooding in heavy rain (usually if this is a potential, the recorded plat will specify minimum finish floor height above mean sea level). It's not rocket science, but it's important to get it right.

I have never seen any "rules" for grading, but it's a good idea to follow the contour of the property. A good rule of thumb is 1/4" in one foot that is the rule for drainage pipes. Look for high spots and try to imagine where the water will congregate and slope it away from the house. If the contour of the property dictates a steeper grade follow that instead.