Federal
Federal Register
National Endowment for the Humanities (NEH)
FedStats - A gateway to statistics from over 100 U.S. federal agencies
Department of Health & Human Services Grants and Funding
National Science Foundation
Department of Education
Grants.gov

State and Local

Funding Resources in Pennsylvania
Center for Rural Pennsylvania  
NewPA.com Funding & Program Finder
Pennsylvania Council on the Arts (PCA)
Pennsylvania Department of Education (PDE)
Pennsylvania Department of Environmental Protection (DEP)
Pennsylvania Humanities Council (PHC)
State System of Higher Education (SSHE)

Foundations
The Foundation Center
Pittsburgh Area Private Foundation Web Site

Organizations/Associations
Research Funding Opportunities via National Council of University Research Administrators (NCURA)
Sigma Xi - The Scientific Research Society
Grants Web via Society of Research Administrators (SRA)

SRU only
GrantSelect - site must be accessed from a computer on SRU campus

All Funding Sources
Grants Alert - a resource for finding grants of all types; Grants Alert also has an email notification service
Michigan State University's Grants and Related Resources Guide - a resource for individual research grants, nonprofit grants, grantsmanship techniques, and more

E-mail Alert Services
GrantSelect
National Science Foundation
US Department of Education
National Institutes of Health (NIH)
The Foundation Center's RFP Bulletin
National Center for Environmental Research
Grants.gov