4 links
Gramineae in the Families of Flowering Plants
delta-intkey.com
Contains list of genera (without links) and some unique illustrations.
Manual of Grasses for North America
herbarium.usu.edu
Information about and from a project creating a taxonomic account of all grasses that have been found growing without cultivation in the continental United States and Canada plus, …
Poaceae in Flowering Plant Families - University of Hawaii
botany.hawaii.edu
Photos and short descriptions of about 20 grasses important in Hawaii.