An Introduction to amino acids:
Part of the University of London , The Birkbeck School of Crystallography performs first class research in structural biology, bioinformatics and materials science as well as offering innovative teaching (including online courses) to a broad audience. This is a good introduction to amino acids including an anatomy lesson of proteins, stereochemistry, the twenty most common amino acids, and peptides.
Overview of amino acids:
Lists the 20 most common amino acids including abbreviations and linear structure formulas. Each amino acid name links to more in-depth information about the aa, including 3D models.