ChemGlobe: Beryllium - Electronic, thermal, and steric data along with basic information. - http://partisans.spurious.biz/~pkremer/projects/chemglobe/ptoe/_/4.html
LANL: Beryllium - Sources, properties, uses, and handling. - http://periodic.lanl.gov/elements/4.html
Wikipedia: Beryllium - Properties of the element, including its history, applications, and charateristics. - http://en.wikipedia.org/wiki/Beryllium
Lenntech: Beryllium - Physical data, chemical properties, health and environmental effects. - http://www.lenntech.com/Periodic-chart-elements/Be-en.htm
EnvironmentalChemistry.com: Beryllium - Atomic structure, chemical and physical properties, and table of nuclides. - http://environmentalchemistry.com/yogi/periodic/Be.html
ChemicalElements.com: Beryllium - Basic information, atomic structure, and table of isotopes. - http://www.chemicalelements.com/elements/be.html
USGS Minerals Information: Beryllium - Statistics and information on the worldwide supply, demand, and flow of beryllium. - http://minerals.usgs.gov/minerals/pubs/commodity/beryllium/
Radiochemistry of Beryllium - Full text of the monograph by A. W. Fairhall (Dept. of Chemistry, University of Washington, Seattle, Washington). [PDF] - http://lib-www.lanl.gov/cgi-bin/getfile?rc000045.pdf