Twellow — A Twitter business and service directory, sorta like the Twitter yellow pages.

appTracks: Web
appTags: business, directory, service, yellow pages

Twitzu – Promote your business, special offers, promotions, and events.

appTracks: Web
appTags: business, events, promote

Twibs – A place for Tweeps to find businesses on Twitter.

appTracks: Web
appTags: business