Ham Radio SatelliteĀ 

a list of some of the more popular ones and their typical uplink and downlink frequencies:

This list is by no means exhaustive, and it's always a good idea to check with local and international ham radio societies or specific satellite organizations for updated frequency and satellite information. Frequencies, modes, and operational statuses can change, and new satellites are frequently launched, so always consult up-to-date sources before transmitting.