This is almost like a parent trying to pick his favorite child...

Here are some of my favorites:

Irish Street Ballads and More Irish Street Ballads, O Lochlainn

Sam Henry's Songs of the People, Huntington, Hermann, Moulden

Bothy Songs and Ballads, Ord

Traditional Singers and Songs from Ontario, Fowke

Shantymen and Shantyboys, Doerflinger

Songs of the American Sailormen, Colcord

Shanties from the Seven Seas, Hugill

I'm also very fond of a number of books mentioned above such as Belden, Sandburg, Cazden, Lomax, Flanders, etc.

All the best,
Dan Milner