I sell them at http://www.furrybabyfashions.com/collars.htm. Scroll down towards the bottom.
You could just use a carabiner, they're found at most hardware/sporting gear stores and come in some pretty funky colors.
Picture on this site:
Baloo - 5 year old black lab
Peanut - 7 year old minpin
Monster - 3-ish year old frenchie/jack, rescue
Is this it? It buckles
Rusty, Blaze & Buster Brown
BJ - 3/9/2007 - 2/6/12 - miss you everyday
Boomer - ? - 3/15/12 - always in my heart
Lori also sells them at 3 Dirty Dawgz...
The 'tag-it' is the best ever. It's really easy to switch over and the tags don't fall off.
Becca & Phoebe
Yeah, I would buy it from Lori http://www.3dirtydawgz.com/tag-its.html