Enya’s sister, Maire Brennan (aka Moya Brennan) has similar music that has been promoted by the Contemporary Christian community. She was a part of Clannad too.
Celtic Woman has been sold in Ignatius’ Press catalogs (even though there is nothing explicitly Catholic about their music, and even though Ignatius Press consistently ignores explicitly Catholic artists in place of Elvis Presley… but that’s another topic altogether).
Iona (not to be confused with GIA’s “Iona Community”), and its lead singer, Joanna Hogg, have fantastic recordings with a soothing Celtic feel.
Seek out “Deep Still” (and its sequels)–a joint effort including Hillsongs’ Darlene Zschech and Ceili Rain’s Bob Halligan Jr, for contemporary praise songs with a Celtic feel (some more soothing than others).
Jeff Johnson is also well worth seeking after, including his “Psalmus”.
A few years back, the CCM community promoted “Streams”, which Moya Brennan is on, and is an exceptional album with tons of great artists, including a fantastic song with 4Him and Jon Anderson from YES.
Also, Michelle Tumes’ albums, particularly her first album.
Lastly, check out Michael W Smith’s “Freedom”–it’s an instrumental record, very classically-based, recorded partially with Ireland’s Philharmonic Orchestra. It’s very, very good.
And did I forget to mention John Michael Talbot? With fifty albums to his credit, he has a series of instrumental albums “Pathways”, as well as “Empty Canvas” that are quite soothing. His most Celtic-flavored offering is “God of Life”.
P.S. I’m openly wondering if ejreydrum drinks Folgers’ Crystals. I mean, they say it’s not reallly “crystals” in the New Age sense, but you never can tell…