The way to go these days with seo is White Hat only. You can't get ranked a website anymore by just building backlinks with softwares, Google knows about this and surely has done something about it. However, it also depends of the niche. If you're in a niche where all the domains have only low quality backlinks then I don't think it would matter if you get some as well too. But if you're thinking of getting ranked in a niche/keyword of quality, then you can't get this done by only getting those free links. Always look at what your competitors has as backlinks and try to copy them.
The way to go now is only to build quality links and naturally. It's going to take a lot of time, I would say over 2-3 months and even more depending on your niche. Plus, you don't even get to see the results as fast in the old days. Google is doing more attention about those Internet Marketers who just wants to make money and won't give you the real rankings you should have after only a few months once you've passed the sandbox if you've just started building links. What I mean is that, if you're just starting out on a new website, you won't get to see your real results only after you've passed the sandbox.
Black hat is dead. You can't anymore just send free backlinks to your website and get it ranked in first page. You have to get quality and trusted backlinks.
The content that you have on your website is a lot important as well. Google wouldn't want to have a website with poor content which gives no values to the users to get ranked in first page.
So yeah, there has been a lot of changes these last years and these are only a few of the factors. Only a few persons today knows how to get this done. Google changes and you have to adapt your strategies, however once you do it, you profit big!
Don't give up, good things comes to those who works their ass off. Always look for more information and try to learn as much as you can. The more you can understand the better you can play the game.
One other thing, you have to be very, very patient if you're doing seo.
Good luck!