[center][url=http://www222.pair.com/sjohn/blueroom/demog.htm]Medieval Demographics Made Easy[/url][/center]

[center][url=http://www.britannica.com/EBchecked/topic/205583/feudalism]General Things on Feudalism[/url][/center]

[center][url=http://www.history.ac.uk/reviews/review/1571]Brief Abstract on Medieval Economics[/url][/center]

[center][url=http://gbtimes.com/life/knights-templar-and-international-bankings-origins]Knights Templar and their System of Banking[/url][/center]

[center][url=http://www.shsu.edu/~his_ncp/Cruslet.html]Letters Written During The Great Crusade[/url][/center]

[center][url=http://historicalsociology.files.wordpress.com/2011/08/teschke-benno-1998-geopolitical-relations-in-the-european-middle-ages-history-and-theory.pdf]Political Relationships During the Medieval Ages[/url][/center]

[center][url=http://www.medievalwarfare.info/]Medieval Weaponry/Tactics[/url][/center]

[center][url=http://www.elfdict.com/]The Linquist Tolkien's Fictional Elvish Speech[/url][/center]

Haven't had time to check them all out, just yet, well besides the demographics, and Tolkien. But this seems like a suitable list of some basic research materials if you do decide to reboot.