Here are some free resources to help you with Twitter.
If you are looking to build your follower list, this is the place to start.
My favorite is Twitter Karma...
You can see who you are following and see when they tweeted last. I had one account where I had 1200 followers and I was following 1150. When I checked I noticed that half of them had not tweeted in a month or more. Why follow someone who is not tweeting. They probably only set up their account as a promo. Weed out these and make room to follow active people.
I have a link for all these on my website in my signature if you need them.
Twitter Keyword Research
Twitter Desktop & iPhone Downloads
Free Twitter Backgrounds
Cool Twitter Images
Twitter Buttons
Hashtags
Tweetlater
Twellow
Who Should I Follow
Using Karma
TwitterFeed
Ping Your Twitter Feed Using Pingomatic
Ping.fm
BudURL
Twit Directory
Twitter Analytics On Your Profile And On Others
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