CBDNet - Notices of proposed government procurement actions, contract awards, sales of government property, and other procurement information.
FedBizOpps - A Government-wide electronic posting system that features a central government-wide index, and an application that allows buyers to post notice of procurements, directly, to the internet.
GSA Publications - General Services Administration Publications, including Federal Acquisition Regulations (FAR) and Federal Information Resource Management Regulations (FIRMR).