A couple of weeks ago, satellite imaging company Planet launched a flock of 48 ‘Doves’, their low cost imaging satellites. They managed to capture imagery of the launch from one of the Doves already in orbit:
As far as we know, this is a satellite imaging first. The key to the achievement was already having a large number of satellites in orbit which enabled them to task a suitable satellite to capture the launch. Even so, they had to tilt it in order to get the shots.
Google Earth features many planes in flight in its imagery. Simply look through historical imagery near any busy airport and you will likely find several. So why is it so hard to capture satellite launches? Put simply, because they are so rare and very fast (the above YouTube video is just 11 seconds long). The chances of a satellite being overhead and capturing an image at just the right time are close to zero unless it is planned in advance as was the case with the Dove satellite.
If you are interested in launch statistics, the website Spaceflight Now has a launch schedule which shows planned launches and we found Gunter’s Space Page which summarizes and categorizes launches. It is possible that there are also classified launches not listed on the above sites.
Satellite launches are unlikely to ever be captured in aerial imagery as aircraft will be excluded from the launch area during launches for safety reasons. Video of launches captured by drones is becoming quite common, but this is not the sort of imagery that is suitable for Google Earth.