I bought this same one at a quilt show. The guild members putting on the show made them for their boutique. So far it is the best one I have used. It does slip a little though now and then but I think that might happen when grass or dirt get under it. Here is the link to the free pattern:
http://so-sew-easy.com/non-slip-sewi...oot-pedal-pad/

Twillibee has the right idea. Make your own. The second link she gave is great: http://so-sew-easy.com/non-slip-sewi...oot-pedal-pad/ I've used this tutorial and made 2 of these for myself and one for a friend and they really do the trick.

I have the Martelli & it works great! Purchased during 1 of the 1/2 off sales.

I gave up using mine. Now I just use the "start & stop" button on my machine. Works for me!

To keep my pedal from moving on carpet, I placed the "hook" side of a piece of heavy duty Velcro tape on the underside of the pedal. The hooks grab onto the carpet keeping It in place.

Has anyone tried a mouse pad? It just came to mind, I haven't tried it yet, but it might work and is relatively inexpensive.

Get some shelf liner, cut bottom 1 piece for bottom and 1 half size,sewing binding around it and your are set; The half top part is to slide bottom of foot pedal for better stability, works great. I carry mine with me in my traveling sewing machine and have one at home. Just be sure you cut it slightly larger than foot pedal .

The long Command Valcro picture hangers work on a hard wood floor. a piece or two on each (floor and petal); on carpeting I use only one side on the petal that will grip the carpet. It works for me. I use Command hooks a lot!!

I bought a black rubber mat really cheap and cut it in half, so I could use it for two machines. It slides a little, but I can move it back really easily and like I said, it is really cheap.

I have the one from Martelli that I bought during one of their half-price sales and it works good.