Here is the one I recently purchased as many recommended it here.
http://www.michaels.com/art/online/displayProductPage?productNum=gc0586
HTH
Hey guys, I have a little tip that I just found out.
I couldn't find a clay gun anywhere to save my life so I figured why not use the "playdough" fun factory extruder thingeebob. I bought one and It worked great for making those long snakes. I used the wilton fondant in it and it worked great. It also had a dye for making a rop with ridges, you twist it and it looks great. I used it on the marine corps cake i just posted.
Here is one on amazon.com:
http://www.amazon.com/dp/B000BUR200/?tag=cakecentral-20
Here is one on amazon.com:
http://www.amazon.com/dp/B000BUR200/?tag=cakecentral-20
This is the one I purchased today and OMIGOD it is hard to use. Please tell me there's a secret I'm missing! 
Ok here is the thing i have used the silver one with fondant and with modeling chocolate (this one you can see in my pics it is the fishing basket.) The fondant is easy to push through, as long as it is warmed up.
the m/c is much harder.....this is what i did.....i used the side of my butcher block stand, place one of the finger spots on the actual extruder agaist the flat sturdy surface,and a flat book placed behind the plunger. You may have to hold it a little with one hand. now with the book behind the plunger use your body weight to push. I know it sounds complicated but it does work.
I have heard of other ways like purchasing a caulking gun and putting the extruder in that. (have one just have not tryed it yet. 
)
i hope tha make sense to you. if not ask me what part you don't and i will try to explain it better.
I have the extruder that was mentioned above aswell as the Makins. I use the little silver one all the time! I get my fondant/gumpaste soft w/crisco, put crisco on the inside of the barrel also. The only time I have a hard time is on very thin ropes or the small "hair disc" all I do in that case is go slow and try not to wear my hands out! Also, when "reloading the extruder make sure you clean the blob that has accumulated on the plunger. HTH Don't give up just yet!
Elle
I haven't had any problems with my Makins extruder. I did have problems with the one mentioned above and the playdough fun factory. I about killed my hand with the silver one and I sent the playdough fun factory sailing across the room (and not intentionally although I would have liked to sail the silver one across the room!!) I probably didn't have my fondant softened enough though either. To me, it was worth it to invest a little bit more and get the Makins. Since you can purchase these at Michaels and Hobby Lobby, you can use a coupon!
Here is one on amazon.com:
http://www.amazon.com/dp/B000BUR200/?tag=cakecentral-20
This is the one I purchased today and OMIGOD it is hard to use. Please tell me there's a secret I'm missing!
I haven't tried using mine yet. It's still in the package 
Just in case you need help pushing your clay gun I found this the other night when I was looking for patterns to use. http://www.kelliesklay.homestead.com/pusher.html
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