The Fiddler's Companion entry for this gives the following verses:
SUGAR IN MY COFFEE
Go there once and go no more
If they don't give no sugar in my coffee-o
How in the world's the old folk know
That I'll take sugar in my coffee-o
Sugar's high and sugar's low
But I'll take sugar in my coffee-o
How in the hell's the old folk know
That I'll take sugar in my coffee-o
It refers to versions by Uncle Dave and Fiddlin' John and gives a precursor from Talley's 'Negro Folk Rhymes':Sheep's in de meader a-mowin' o' de hay
De Honey's in de bee-gum, so dey all say
My head's up an' I'se boun' to go
Who'll take sugar in de coffee-o? (Similar to Uncle Dave Macon's lyric)
I'se de prettiest liddle gal in de county-o
My mammy an' daddy, dey bofe say so
I looks in de glass, it don't say, "No"
So I'll take sugar in de coffee-o. (Close to John Carson's lyric)
You'll find the full entry here:
--Stewie.