Subscription-based:
SPIN Database - Office of the Provost currently provides an institution-wide subscription to SPIN funding opportunity database. SPIN offers a wide-ranging funding opportunities database with over 40,000 programs from more than 10,000 unique sponsors. Visit SPIN.

Open Access:
Grants.gov – where all discretionary grants offered by federal grant-making agencies can be found
NIH Guide for Grants and Contracts
NSF Funding