Great information from Maryland Cooperative Extension: http://www.hgic.umd.edu/_media/documents/hg69_003.pdf
This link takes you to the State's research and extension page for grapes and fruit. Technical information as well as updates on activities and issues in Maryland.
Information on all things fruits and berries from Penn State http://agsci.psu.edu/fphg
Maryland Cooperative Extension http://www.hgic.umd.edu/_media/documents/hg76.pdf
How to's for berries and grapes: http://www.hgic.umd.edu/_media/documents/hg68_000.pdf
Excellent website with information and links to all things growing and gardening: http://www.hgic.umd.edu/index.cfm
Article on what trees grow well in Washington, DC, our neighbor to the south of us, with lots of great links: http://www.dc-urban-gardeners.com/2008/11/fruit-trees-for.html
Excellent website from the EPA on urban agriculture, including how to farm on brownfields, with links to federal, national and local resources: http://www.epa.gov/brownfields/urbanag/resources.htm