Before Sirius, before XM, before almost most any non-military satellite, you had OSCAR-1. OSCAR is an acronym for Orbiting Satellite Carrying Amateur Radio. OSCAR-1 was launched on December 12, 1961 just 4 years after Sputnik-1 was launched. Sputnik-1, by the way transmitted 20 and 40 MHz and thus was monitored both by the military and amateur radio operators. OSCAR-1 only lasted 22 days in orbit but hundreds received its VHF signal.
More than 70 amateur radio satellites have been launched since. AMSAT (Radio Amateur Satellite Corporation) took the reins from Project Oscar in 1969. Their website has information and tracking for current satellites.
Which brings us to AO-51. It was launched in 2004 and functions as an FM repeater and a BBS. To listen to a LEO satellite such as AO-51, you have to both adjust the frequency for the Doppler Effect and track it in the sky with a directional antenna.
And audio I recorded this afternoon: