The e-tailer Amazon has begun selling WiiWare titles on their website, allowing users to buy the games for the first time outside of the Wii Shop channel.

However, Amazon has not officially announced the store and so far the only game available is World Of Goo. The game may just be a test to see popularity, before a dedicated store is created.
Link: http://www.afterdawn.com/news/archive/17724.cfm