Thanks, but I'm not sure what I need to be careful about
My ears will usually tell me if a chord is incorrect, and I already know the correct/original lyrics of most songs I'm likely to sing. In any event, if the lyrics aren't 100%, who'd know if I was merely playing for myself in my living room?
Copyright questions should be addressed to the owner of the site; I don't take any of their stuff and re-distribute it. I see that a number of their songs are linked in from other sites and due attribution given; This is not like file sharing, and there's nothing illegal about linking content. In other cases, music has been written/rewritten/rearranged by a third party and submitted to the site, and again due attribution is given. Best ask the site owner about the legality of doing this.
Meanwhile, I have a bookcase half full of 'legal' songbooks and loose music scores that I've purchased over the years, including a bunch of ukulele songbooks that I've purchased in the last 10 months or so that I've been playing the uke. I've also built a small collection of (legally purchased) mp3 tracks of uke songs to help me learn the music to some of the songs I was unfamiliar with.