I'm not 100% sure, but I believe you can by Lens Babies for all makes of DSLR's. But, pls wait for someone who uses them, to give you a better answer. In the meantime, I'll do a little research and see what I can find out.
But, I would like to know, what kind of equipment do you have? It would be a lot easier to research for specific cameras.
I've been using a Lensbaby Composer for about a year now. I don't think I'm a great Lensbaby photographer, but it is fun and a good creative option - more so for some photographers than others. I just checked the Lensbaby Web site and the Composer is available with the Pentax K-mount. So if you have a Pentax or Samsung digital SLR, you could use the Composer on your camera. Here's a link to all the Lensbaby reviews: