1. Wait for the HomePod: https://www.apple.com/uk/homepod/
2. New Sonos that come with Alexa (I'm not sure if it's full-blown Alexa though): http://www.sonos.com/en-gb/shop and then: http://www.sonos.com/en-gb/apple-music-on-sonos
3. Buy an Echo: http://amzn.to/2yTPRdV and use the Bluetooth...
The definitive NSC thread: http://www.northstandchat.com/showthread.php?345597-Amazon-Echo-Alexa-music
Buying links (affiliated, obvs)
Black echo: http://amzn.to/2vxTsOe
White echo: http://amzn.to/2vN2aYg
Black dot: http://amzn.to/2uoby4N
White dot: http://amzn.to/2uNoAuS
Prime music...