One of my favorite Twitter marketing tools is TweetDeck. (http://tweetdeck.com/beta/) It's a better way to use Twitter than Twitter itself! If you are using Twitter in your marketing, TweetDeck allows you to view all your relevant info in one simple console. It's a free download, and currently considered beta software, but I haven't had any technical problems with it.
I use four columns on my TweetDeck application: All Friends, Replies, Direct Messages, and Search.
All Friends. This column displays all of your friends tweets, in real time. I usually open TweetDeck once or twice a day, so the first thing I do is scan all my friends Tweets, looking for anything interesting, funny, or noteworthy in any way. I have found a lot of great tips, websites, quotes, and other ideas just through scanning this column. If I find something I really like I will re-tweet it. TweetDeck makes it easy, all I have to do is hover my mouse over their profile pic, and it gives me the option of reply, re-tweet, direct message, or favorite their Tweet.
Replies. This columns displays all replies to me personally, as well as any re-tweets. I always Direct Message those that re-tweet my stuff, thanking them for the re-tweet. I don't usually reply, as that would appear in my Twitter stream, and I have my personal Twitter presence linked to my Facebook profile, so I don't want to "clutter up" facebook with a ton of personal back and forth Tweets.
Direct Messages. Let's face it, most of these are automated spam. I ignore those. But I do scroll through to find the "real" DM's, and respond to those. Some people think Twitter is an online version of Instant messaging. It's not. You don't have to respond instantly to everything that's sent to you. Don't feel bad about responding to messages a few hours, or even days old. Twitter is a micro-blog, nobody should expect instant communication back.
Search. In this column I see results for any key term I'm interested in. I currently have the name of my company. If one of our affiliates is sending out a Tweet about it, I will often re-tweet their message, exposing their link to all of my followers, and letting them know I appreciate their referrals. Other mentions include simple things like, "Listening to a training by..." and I respond to those too. Any publicity is good publicity, so I try to thank anybody who's putting in a good word for what we're doing.
The key is to be consistent, and to use TweetDeck as a part of your overall Twitter strategy, helping you drive traffic, build relationships, and stay in touch with prospects and clients.
Dave Sherwin is the co-founder of the Lighthouse Marketing System, and author of "Twitterpated! The Savvy Marketers Guide To Twitter" Get the guide FREE at his blog: escapethematrix.net/blog