How about the Folk song and Ballad Index?

Here's what it says about Loch Lomond, for example:

Loch Lomond
DESCRIPTION: Singer laments parting from his/her love by Loch Lomond, noting "the broken heart it kens nae second spring." Chorus: "You'll take the high road and I'll take the low road And I'll be in Scotland before ye But me and my true love will never meet again..."
AUTHOR: unknown
EARLIEST DATE: 1841 ("Vocal Melodies of Scotland")
KEYWORDS: loneliness love parting separation Scotland lyric
FOUND IN: Britain(Scotland(Aber)) US(MW)


1841. It's pd.

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Somebody here said that there could be a copyright on the chords. I don't believe that. I've read a lot about copyright, and I have never seen the word 'chords' anywhere.

Chord symbols aren't music, they just suggestions. If you took five groups of Mudcatters and handed them all the same song with the same chords symbols, you would get five arrangements. If you waited two weeks and did it again, you would get five more.

Keep in mind that while there are penalties for infringing copyright, there are no penalties for claiming a copyright that one is not entitled to. I see ridiculous claims to copyright rather often.