Before you flip to another blog page as you might be moaning over that title,let me assure you that songs will open up to you if you learn to read music for your uke,no matter if it's soprano or baritone. Having said that,I am a fan of TAB but it only works for the instrument & tuning it's written for. Learn to read standard notation and here's what can happen:
Seeing as baritone uke is like the 4 upper strings of a guitar,a lot of guitar music books become applicable. Not that you'll be able to play absolutely any tune in any guitar book due to being minus two lower strings,but it opens a lot of doors. And-if you love 1920's tunes,etc,you'll be able to play most of those even tho they're arranged for soprano ukulele.
I'm quite amazed that beginning baritone books never seem to mention these points-they have you learn to read music with really boring tunes but never mention the true reward. (because the old ditties they use,while dull as dirt,are public domain which means no concerns over copyright infringement) In modern english,you may not be all thrilled to learn to read the notes to play "Twinkle Twinkle Little Star" but that can lead to you being able to play "Stardust" "Darktown Strutters Ball" and a host of others,including modern tunes by your favorite groups.
In other words,you're no longer beholden to "arranged for baritone uke" sheet music & song books.
Don't forget right hand technique guitar books,either. Flatpicking is flatpicking even if done with a felt pick and on your bari-right hand technique is basically the same,as are bass runs from one chord to another,so on & so forth.
The pic of the baritone book you see to your upper left is a wonderful primer for reading music-click on the book and you'll be taken to where you can get a copy at a discount.