I have only found one or two free patterns, but I have a good collection that really hasn't cost me much. If you buy anything (and they sell single designs if you only want one) go to
http://www.emblibrary.com and put redwork in the search. Once you have bought something, you get frequent special offers when you might be able to get 10 single designs for $10, or everything half price, or some other variation on savings. I hope that helps, this company has more redwork designs than most, as far as I can see.
Put everything in your wish list, and wait for an offer to come along!