LL -- The Sain site shows that Teulu'r Tir is only on tape - I've just been getting the cd's - but it does have the great song, "Yn dewach na dwr." Myrddin ap Dafydd's story (I think) of the soldier from Wales who meets a Patagonian Welsh nurse during the Falklands kertuffle - I still haven't figured out all the words - I think their best song is Seidr Ddoe.
You can hear Plethyn and other Welsh music on the radio Acen site - an mp3 recorder would let you hear it at your leisure.
Hope that you enjoy the music. For the St. David's Day Dinner, myself and two others are doing some Welsh numbers, including Lleucu Llwyd, Y Chwarelwr, and the Welsh version of Red Rose Cafe. We are also singing all 3 verses of Mae Hen Wlad in Welsh - the practice in the past was for them to sing it in English - there'll be no more of that on my watch!!
Sian - I hope that more Welsh groups can get to all parts of the US - especially Chicago. We get the rock groups here, but not the folk groups, although Ffynnon was here last year for the Celtic Fest - you could contact the City of Chicago and help them pick more great Welsh groups for that annual event.
Hwyl, Chris yn Wheaton