The only song I know by her (besides IWALY) is "Coat of Many Colors," which I absolutely ADORE!
I've been meaning to dig deeper into her catalog, but I have no idea where to start. Any suggestions?
The country landscape doesn't change as often as pop, so you can start in a lot of different places. Her early duo stuff with Porter Wagoner is middling, in my opinion. If I were you, I'd go straight into the Jolene album or the 9 To 5 And Odd Jobs album. If you enjoy modern country (Miranda and Carrie, especially) then her newer stuff like Blue Smoke and Backwoods Barbie might appeal to you. Better Day, too, but it's a bit more gospel-y than the others.
My personal, all-time favorite song of hers, though, is a soundtrack single she did for the film Transamerica. The song is called Travelin' Thru, and it's ridiculously inspirational. Some of the best songwriting I've ever listened to.
Two doors down, they're laughing and drinking and having a party!
Two doors down, they're not aware that I'm around, 'cause here I am.
No longer crying and feeling sorry; we're having a party just two doors down!
Could you narrow it down a bit, please? 
...cuz I'm making loads now
