Our local Q & A newspaper columnist had an answer to this a few columns back. The first answer won't help you much, as the organization only accepted used cards through yesterday but she said there are others whose names she can supply if you email her. Information follows: "St. Jude's Ranch for Children, Card Recycling Program. 100 St. Jude's St., Boulder City, NV 89005. Cards accepted through February 28, only. There are other organizations which accept used Christmas cards but not all of them have given me permission to list here. For a list, send an email to jmorris@bayareanewsgroup.com and put "Christmas Card Recycle" in the subject line."
Hope that helps!