I may not know much about backlinking, but as far as i know, using a bot or a software to do it may cause harm to your SERPs.
If you're going to spend money on links, I'd say just purchase high PR blogroll links directly. Quality over quantity
if you are interested in spending money then i think spending on some software is not a good idea. i think you should get some featured links i the high PR directories. like PR 6+. these links will be one way and will pass a huge juice to your site. and if you get good place to display your ads then you will get a huge number of visitors from that directory. thanks
I think we should not use any software to build backlinks because according to google policy it is prohibited and can damage your ranking in search engine. We should concentrate to do manually work and in this way we can rank our site rapidly and in ethical way.
I knew the basic principles of getting backlinks to get traffic. I just did not want to spend my time doing all the work.
The best software to make backlinks is real humans (fiverr) ... I mean outsourcing. Unless you have only one website, you find yourself bombarded with the task of building links...even with a software. But if you are someone that has the time, I recommend unique article wizard, social bookmarking demon, and senuke x
Making links manually is the best option. So go for that, it takes time but give long term results. Google also like manual link building, don't like softwares and spammers.