Not sure that's the right place for something that's a general accessory.
The More Information section seems more appropriate and is a user-maintained wiki. Any BGG member can edit the wiki and enter the info there. IIRC, some games do have sleeves listed.
You recall correctly.
You can start here http://boardgamegeek.com/wiki/page/Card_Sleeves# & then make your way to the games that are linked. See Le Havre and London as examples.