Many people choose natural stone that has been quarried from the environment around them, or from another location.  If you use limestone you will get a gray stone or brownish color that blends nicely with the surroundings and comes in rectangular pieces.  It is four or five inches thick and can be used for pathways or steps.  It can be used as for patio surfaces and in thousands of landscape designs.  You might also want to choose sand stone or field stone.  They are beautiful and functional, and can be used on the exterior of any structure, for retaining walls, to identify planting beds or field stone  can be placed in groupings to enhance the landscaping plan.  Any kind of reclaimed stone or landscape stone can be used in pathways and to surround plantings and stop the invasion of weeds into your garden.  Check out this web site for some great ideas, to use with granite, if you chose, for a great looking yard.http://www.selectstone.com/.