Kate Yes I got an Echo and Echo Dot for Xmas. My DS has paid the subscription for the music options for me but I too have not got much further than asking for music and the weather, oh and radio stations.
My DH gave me a list of questions to access music etc, try these
Alexa play children's music
Alexa play the top songs from 1994 to 1998
Alexa play the Top pop station
Alexa turn it up, what's playing, stop the music, repeat the song, set a timer for 30 mins, volume 4, tell me a joke.
I haven't worked out yet how to make my own library of music.
Hope the above helps. From another Kate.