press releases used to be one of the best and fastest ways to get backlinks. Get your PR on the front page of Reuters, AP, CNN and BBC and you're almost guaranteed a flood of millions of eyeballs and possibly 1000s of links within a week. But it would be very expensive... and you'd need news-worthy content that these big media outlets starve for, so this doesn't work with "niche sites". But if you have a business or innovate / discover something... well, you can figure out the impact yourself
why not? Networks like Adsy.com, for example, are good, they've helped me rank my website about 4 years ago (albeit for a medium-difficulty keyword, but I also didn't buy too many links either, I think 3 or 4 and after I indexed the links the keyword went into top 20 from nowhere within days).
Link networks are OK to use (until google kills them off that is, it's happened to the biggest and best link networks of the past)
Another link building network that could work (I say "could work" instead of "will work" because I never got to try it out despite of the fact that I've been offered a free trial when they've come on the market) is RocketGuestPosting.com, but this is more of a database of link building sites instead of link building network per se.
But if you have the money, time and dedication to look through their inventory and contact those sites you might be able to get a few dozens quality links within 1 month and - let's be honest - for most SEO newbies that's all they need to see results and be happy with their sites (at least for me this would work, I never aspired to become a millionaire and - truth be told - with today's google you can't achieve this anyway unless you're already rich enough to be able to abuse google's policies and loopholes)
Anyway, give networks a try, you might be pleasantly surprised
5.3 backlinks over 2 years means 221 backlinks per month, which is roughly 7 links per day. Very doable... And yes, it might cost a lot, but SEO is a rich man's game nowadays so you shouldn't be surprised. Also, believe it or not, there are still a lot of people who have tons of money to throw away, and what expensive means for us for them is just bubble gum money...
did you do this manually, or using software?? Because I'm pretty sure that if you use software you can land dozens or 100s of links per day / week (depending on how fast the contacts reply and take on your offer, of course)... or you could try cold emailing services like Postaga (never used them, I've gotten their AppSumo deal for free a few years ago, but never got the chance to try it out because I have sold my websites in the meantime... but they seem OK) if you've got the cash...
