Khan Academy
Khan Academy: Allele Frequency & the Gene Pool
Learn how to find allele frequency and how it's different from genotype frequency.
Other
University of Illinois: Population Genetics [Pdf]
This site from the University of Illinois at Chicago provides an in-depth article on Human Genetics, with a focus on primarily population genetics. The article is factual and informative full of charts, formulas, and extensive text. A...
University of Maryland
Univ. Of Maryland Baltimore Cty/biology Century
Historical perspective on Mendel's contribution. Spends a little time setting up what the current beliefs of Mendel's day were and how he changed things with what he did.