This is one of the best all around sites that
I have found. It is titled "The MacTutor History
of Mathematics Archive."
http://www-history.mcs.st-andrews.ac.uk/HistTopics/Zero.html
This is an
award-winning site that links to all sorts of mathematics
information.
http://archives.math.utk.edu/
This is an
enrichment site on Babylonian and Egyptian mathematics.
http://www-groups.dcs.st-andrews.ac.uk/~history/HistTopics/Babylonian_and_Egyptian.html
This is a very
good historical site called Mathematicians of the
African Diaspora.
http://www.math.buffalo.edu/mad/Ancient-Africa/mad_ancient_egypt.html
This site provides
links to other Egyptian and Mesopotamian mathematics.
http://www.gap-system.org/~history/HistTopics/Babylonian_and_Egyptian.html