The Maid of Coleraine?

I used to be in a band that did (I thought) a nice acoustic version of Led Zeppelin's rain song. It lends itself to a simple arrangement rather well.

haven't read every last post above, so sorry if these have been mentioned;

Rainy night in Soho - Pogues
Anything by Wet Wet Wet
(getting desperate now, so will shut up.)