http://www.chaosium.com/
http://www.tccorp.com/outsider/doll.html

Evil, slimy, horriffic...and somehow very adorable....
Please note: Chaosium no longer stocks these (the link stays cos I'm using their photo), but fortunately The Outsider still has the hideously cuddly freaks, in a variety of tasteful colours.
(This information courtesy of Adam Holmes--Thanks!)

A Cthulhu soft sculpture by Canadian artist Sarah Ennals; fancier, freakier and fuzzier than the Chaosium dolls. Photography by Andrew Specht.

http://www.toyvault.com/cthulhu/index.html  

Toy Vault may or may not be out of stock-- you'll have to ask them yourself.
But anyway, here's what their take on the stuffed Cthulhu concept looks like in the catalogue...

http://www.cthulhucoffee.com/

...and here's what it looks like when decorating the Christmas tree of Melissa S. Kaercher, web minion of Cthulhu Coffee (check out the link on the Cooking With Cthulhu page). Nice one!

http://www.logicalcreativity.com/jon/plush/01.html

Once upon a time, all the little creatures of the Land of the Stuffed Animals lived happily together. Until one day, they disturbed the rest of the Plush Cthulhu.... For highly disturbed children everywhere.

This link, once again, courtesy of Miles Gould.

http://www.zompist.com/

One from Mark ("Horselover Fat") Rosenfelder, SpinnWebe guru.
If you're wondering what a "woobie" is, there's an explanatory link at http://leth.50megs.com/archive.html. But remember, you have been warned.

http://www.slavelabor.com/index2.html

Awww... this worried little chap, Carl Cthulhu, is a cartoon character, and now he's a doll!

Carl Cthulhu is seen regularly in the pages of Little Gloomy, published by Slave Labor Graphics. All rights reserved. Carl Cthulhu tm & © 2002 Landry Walker & Eric Jones.

http://www.offworlddesigns.com

I'd back this guy against Baby Kermit, Baby Gonzo, Baby Piggy, and frankly the whole lot of them.

Another link courtesy of Kate the Wench.

A Cthulhu Couture design by Mark C. Farringdon, who very kindly sent it in. Monkey magic!

http://www.toyvault.com/cthulhu/index.html  

...and don't just wear your Cthulhu as a hat, wear him as slippers as well! From Toy Vault, of course.

Link courtesy of Alice Dryden.