One of the useful Twitter websites recommended in "How to Save $100,000 a year on Google AdWords" was Twellow.com. Twellow was a free service that located Twitter accounts via relevant business categories in a specified area and was often referred to as the Yellow Pages of Twitter.
Unfortunately the site and twitterlocal.net appear to have gone permanently off-line and I can find little information on the internet to explain their demise. I suspect the advertising revenue could no longer cover the costs of maintaining the service. For an alternative service take a look at www.localtweeps.com which is still live.
Other recommended tools for Twitter include:
All these sites are all live at the time of writing this post and as promised it's our intention to keep our followers up to date with any changes we become aware of so do let us know if things change or you have found another top Twitter tool you would like to share.