Some link builders spend a significant time just trying to build up some sort of rapport with other webmasters. Eventually, they may feel that the pool is drying out. With so many link requests nowadays, you can't blame but feel helpless since everyone seems to be getting numerous link swap requests daily.
Where else can you go to build those valuable links? Perhaps your scope is too narrow. There are millions of sites on the internet, so look at related sites, local sites, un-related industries that still have some sort of relationship to the topic, how-to sites, blogs, history sites, and more. There really should be no shortage.
And truthfully, if you're feeling limited, perhaps you're also looking for "high authority" sites. Look into sites that may not be as authoritative but still show some promise.
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