Maryland Grass Seed
Seed certified by the State of Maryland for purity can be purchased in large amounts from farm supply or farmer co-op type stores.
For further information about purchases grass seed in Maryland, look on page 4-5 of the following lawn maintenance publication on our website: http://extension.umd.edu/sites/default/files/_images/programs/hgic/Publications/HG102%20Lawn%20Estab...
Click on the link in the publication for lists of specific variety names. Note that it is often difficult to find those specific named seed varieties because the industry purchases them in large amounts.
The entire publication above is a great overview of fall lawn care.