There is a brief (but informative) discussion of Spanish colonial swords from a few years ago that Jim McDougall started:
http://www.vikingsword.com/vb/showthread.php?p=61271 The article on this site written by Lee Jones is also very helpful.
As pointed out by several people in that thread, there is not a vast amount of information on Spanish colonial swords. Even some of the museums in Spain have few examples.
Ian.