How to get on theme links?

Ask any search engine expert about on-theme links and get prepared for the nasty look. It is actually quite difficult to get on theme links. What do I mean by on theme links? Let us say you have a website that sells mobile phones and you want another website selling mobile phones to provide your link for more information on their site. This is known as on theme link as the link provided is based on the same theme.

But in today’s current scenario, no website agrees on on-theme links. Why? Because a link to some other website that deals with the same subject would render your site incompetent to provide necessary details and on the other hand, such links are highly considered by Google and other leading search engines where they give more preference to the site whose link has been provided over the site that provides the link. So this works against the site which had mentioned the link.

This began when Google had started preferring links as an important criterion to rank pages or sites. Prior to that links on the same theme were widely exchanged and given in order to provide more information to the customers and visitors. But with Google considering Links as king factor, competition crept in and that had negative effect on linking.

Webmasters found a way to defeat the issue in hand by exchanging links. This was also known as 2 way linking. But with its astute, Google soon discovered the commercialization of links. It started rendering the 2 way links exchange as useless. This has now brought the whole linking game to a situation now where on theme links are highly discarded.

Today, Webmasters are going for off theme linking where placing a link of another site that is based on a different topic is done. This does not really effect the competition that a site is facing as the themes are different but how can that be helpful is still what I wonder. What do you say?