Whenever I'm looking for a holiday song, I know to check in with Brave Combo. They've got a song for pretty much every occasion. I'm not kidding. This 2005 CD from the eclectic group puts the spotlight on everything from Christmas to Father's Day. It's a great, and very much under appreciated record. You can still get hard copies of "Holidays!" direct from the group. And, as it's nearly Christmas, you can pick up last year's live Christmas CD, "Christmas Present", for the sale price of $10.
To the extent that there's any "Traditional" Thanksgiving song that I listen to at my house each year, this would be it. George Winston's "Thanksgiving" has always been my favorite song from what remains a pretty terrific record. I might even call it an Essential, except I've already updated that page today. You can still get this at Amazon and just about any place else. The classics never go out of style. George's latest is an album of Vince Guaraldi music, including "Christmas Time Is Here". Check it out on his web site.