Are you happy to get the Container Store catalog delivered to your doorstep, but not so interested in repeat mailings from Pottery Barn? A free Web site, www.catalogchoice.org, lets consumers opt out of getting catalogs they don’t want while keeping the ones that they do. The site launched in November. Since then, more than 358,000 consumers have signed up, according to Mary Burnette, a spokeswoman for the National Wildlife Federation, one of three environmental organizations that created the site. The originators of Catalog Choice hope to reduce environmental waste produced by the 19 billion catalogs mailed every year in this country.