I'm wondering if there are any compilations of rare Elton John songs to be found, either to buy online, in stores or from other orgers or if anyone can point me in the direction online where to download some.

I know about Rare Masters, To Be Continued, and the bonus tracks from the remasters that've been done since '95. Anywhere else?

Just like Prince, you'd probably have to hook up with a bootlegger, or do a little research to download them online. What you listed is pretty much all that's commercially available. Of course, it's a little trickier to find some of the b-sides that came out after 1975. Some of them are on the reissues of his albums- but there are many albums that didn't get remastered that have excellent b-sides. You'll just have to do some homework, unfortunately...

I dont really know anything about any Rare Elton songs.. but he's most definitley a great artist!!! - I'm not into bootlegs AT ALL.. but I'd probably have to agree with "Jtgillia" ..