I would watch out for any link building companies that promise crazy results... link building schemes are generally frowned upon by google and other major search engines. They may even blacklist you if you link with too many sites like that. The best way to do it is old fashioned searching the internet. You can post on blogs and forums (related to your field is better) that are high PR and usually get a link to your site with related keywords, if you post quality content. You can also buy links from related sites that come up good in search engines, thats worked great for me many of them come up good and only charge a minimal yearly charge to list on their website. There are lots of decent directories that may have one time charge, and many free ones though you have no guarantee getting listed on those (and usually not on paid eithre, but much better chance).
My understanding is that if you are getting too many backlinks all at once that appears abnormal to the search engines you will not experience the success long term you may be expecting.
Building links is a never ending job for me, I don't trust link building companies as you need to check the links anyway, for an extra 1 minute you could put the link there yourself. I find putting a link list on all my sites helps as well, I provide my own backlinks through my network of sites. I used 2 different link builders and both failed miserably. Try and get 3-5 links a day yourself and before you know it you have hundreds of them. Best wishes ODA
Getting backlinks is only the beginning - getting backlinks indexed is another story. Thousands of backlinks are no good at all if they are not indexed. It is far better to get a few backlinks and concentrate on getting Google to index them.
I don't think so that it is out dated but in current scenario if you will make huge number of backlinks in a short period then you can get penalty..