Link Building must be done carefully, and always by a human and not by software. Software should be used to monitor the links, to check websites' rankings, PR, Page Authority, Domain Authority, Website Age, etc....
In my opinion using tools like Senuke ,Xrumer, Scrapebox etc is wasting of time and money if you think about earn big money. I am in SEO business since 2005 and used most of the best tools wich was invented since then including Senuke and can tell you they aren`t so efficient as most of the people say, they maybe works for niche keywords and can rank them fast, but if you want to focus on more competetive keywords they will fail. You will have to work very very long on high competetive keyword to see them in TOP10, there are much faster ways of doing that, if you are interested let me know I can help you, just PM me.
If you don't know how to use these tools, then it's of no use. It is very important to learn how these tools work and it's worth trying. It will save lot of time and effort.