I have personally used TweetAdder3 with success, it wasn't too expensive and there are no monthly fees. I purchased the package that allows you to add as many twitter accounts as you want into the desktop TweetAdder client... I have 12 right now. You can search for other Twitter members to "follow" based on followers of a follower, keywords of their tweets, most recent tweets, basically anything you want. From there you can load in proxies and specify how many follows you want to send a day. THEN you hope those people follow you back, make sure you aren't just spamming them, that the twitter profile you're using actually has content they'll be interested in, etc. One more note, I've found that for every 100 people I follow I get 10-15 follows back... You can always unfollow the people that don't follow you back a few days later (another feature of TweetAdder) I know this probably sounds like a plug, but I'm just a fan. P.P.S. Twitter won't let you follow more than 2k people, until you have at least 2k followers... So it can take awhile to hit that mark before your followers really explode. Hope this helps!