This is my own implementation of the the Snowball system to bootstrap relationship instances. You can find more details here:
Eugene Agichtein and Luis Gravano, Snowball: Extracting Relations from Large Plain-Text Collections. In Proceedings of the fifth ACM conference on Digital libraries. ACM, 200.
H Yu, E Agichtein, Extracting synonymous gene and protein terms from biological literature. In Bioinformatics, 19(suppl 1), 2003 - Oxford University Press
A sample file containing sentences where the named-entities are already tagged can be downloaded, which has 1 million sentences taken from the New York Times articles part of the English Gigaword Collection.
NOTE: look at the desription of BREDS to understand how to give a tagged document collection and seeds to setup the bootstrapping of relationship instances with Snowball, both systems have a similar setup.