[lukaa]

I wonder is there extension that would do exactly opposite, only include google results from sites that i choose in order that i want.

[davehcker]

Ordering is something that I'm not sure about (but I've myself been thinking about it for a future addon- if not the current one) that would 'weigh' the URLs like .edu/wikipedia etc. much higher. Would such a feature be helpful to you? And as a part of the same addon?

As for only results from specific websites, you may use Google Operators (like inurl, site, etc.)

[ranadeep]

Yeah, I'm looking for something like this too. I would like to have Wikipedia at the top of the results.

[wanderingstan]

Sounds like Google Custom Search? https://developers.google.com/custom-search

[ImaCake]

Well doesn't give order, but "cake site:news.ycombinator.com" will give search for keyword "cake" only on HN.