A good tip I saw on here before was following the followers of local news accounts.
Purchase for Followers and thats the better advice.
LOL. If you're doing to make your profile look "more popular", that's fine. But if you're doing to get more traffic and sales, you're wasting your time. That's 90%+ bounce rate kind of traffic if you ask me.
It takes lots of work to build a quality twitter fanbase. Lots of useful tips here: Top 5 Tips to Attract Targeted Twitter Followers - IronMonk (The Hootsuite trick has actually been very useful to me)