Card Games and Solitaire
Offers free solitaire, klondike, freecell, calculation solitaire, pyrimid solitaire, patience and other games you can play online or via download.
http://www.cardgamesolitaire.com/

House of Cards
Searchable directory of traditional and family card games and accessories, software, rules and playing guides. Features online ordering and offers.
http://thehouseofcards.com/

TreeCardGames.com
Browse through a high-quality collection of 504 solitaire card games.
http://www.treecardgames.com/