In the process of finding links and determining which links are actually valuable, Google can play a bigger role than you’d expect. Google can tell you exactly which website is of high quality, is relevant to your website, attracts lots of visitors or can provide lots of conversions. Google can even provide information about the possible monthly value of a link in $.
How? Read on.

1. Use relevant, commercial search queries.
No new information here. If this is new to you, please go read this or this. If your website is about hotels in Barcelona, use Google to search for hotels in Barcelona. Google will provide a list of websites which Google thinks are high quality, relevant Barcelona hotel websites. The perfect material for your link.
All you have to do is Google for hotels in Barcelona and contact the websites that are in the top 50, top 100 or whatever other amount of websites you prefer.

2. Search for related, non commercial websites.
If you have tried the previous tactic before, you’ll know it sucks. If you’re lucky, there might be two websites in the top 100 that are willing to add a link to your website. This strategy can be more successful.
When you’re promoting your website about hotels in Barcelona, search for ‘information about Barcelona’, ‘Barcelona city info’, ‘Catalonia area’, ‘FC Barcelona’ or ‘Spain weather info’. Google will show (mostly non commercial) websites related to this subject and somewhat relevant to your website. Most of these sites might be willing to add a link to your website, especially when you’re able to offer them a ‘reviewing’ fee.

3. Use Google AdWords.
The second tactic sometimes provides a lot of useful websites that -paid or not paid- are willing to link to your website. But here’s the top tactic. Google’s own ad program can deliver very valuable info about which link
a) is relevant to your website
b) can provide a lot of visitors
c) may provide a lot of converting visitors