Accuradio.com
http://www.accuradio.com/radiocelt/
Accuradio is a free Internet Station providing huge number of music categories. I’ve just posted the address for the Celtic channel.
Here’s a link for Trad Irish.
http://player.accuradio.com/player/slipstream/radiocelt/?channel=Celtic&sub=SubTraditional
There are lots more to discover on the website