Congratulations, WIChix.
Actually it is a Singercraft guide. All one word - Singercraft. I have had one a really long time, but did not get the extensions until fairly recently. I used it to make fringe for a lion applique when my kids were little. I think it is sometimes called a rug tool.
A couple of sites:
http://thefeatherweight221factory.com/page21.php and
http://www.knitting-and.com/singercraft/what-is-it.html
Probably a bunch of youtube videos.
Kind of a fun tool.
Janey - Neat people never make the exciting discoveries I do.