I guess you are talking about the best unlimited internet connection, right? because broadband means a minimum of 256kbps speed ...
Is MTNLs/BSNLs unlimited phone usage for internet scheme available in your area? Its a cheap option, and incase your ISP is bad, you can switch to another without much hassle ...
If you want a cable internet connection for cheap, you should see which ISP's are available in your area ... Sify has an upto 48kbps plan for rs 450 ... but the speeds and service is awful ... I have heard hotwire will be starting a similar priced scheme.