I was wondering if you guys know of any resources that will help me play unaccompanied crowd pleasers... not necessarily happy sing-alongs, but more like relaxing, romantic, melancholic music... sorta free-stlye, you know?
I suggest you give a look to Sting....
He has some lovely music, romantic, relaxing and very moving.
I recommend you my favorite song: "Shape of my heart".
Download it and listen to it in a good audio player with the lights off
... You can then search for the chords in google to play it on the piano (I use the guitar chords to then make the arrangement in piano), or you could find the piano version too... (include in your search the word "chords" +" shape of my heart")
If you are looking for that piano-bar style music, then you are probably looking into jazz standards.
"Autumn Leaves" is a nice standard and not so difficult and sounds really nice. "All the things you are" is another one, "Strangers in the nights", etc.
You could also search for "Fake Book" or "Real Book", which contains more than hundreds of songs in jazz chord notation of the most popular jazz songs.
I hope this was useful!