Tantalum-Niobium International Study Center
The Tantalum-Niobium International Study Center (T.I.C.) is an international, non-profit association. It has more than 50 members, which are companies involved in raw material production, processing, assaying, trading, capacitor manufacture, chemical process equipment manufacture, and are situated in more than 20 different countries across the world.
http://www.tanb.org/

Shenzhen Capacitors Industrial Co., Ltd.
manufacturer of chip tantalum capacitors, dipped tantalum capacitors and others capacitors. From China.
http://www.china-capacitors.com/

CAMEC
Tantalum mining in Africa.
http://www.camec-plc.com

LANL: Tantalum
History, production, properties, and uses.
http://periodic.lanl.gov/elements/73.html

It's Elemental: Tantalum
The Element Tantalum - Basic Physical and Historical Information
http://education.jlab.org/itselemental/ele073.html

Nichicon Capacitor Incorporated
Supplier of tantalum and aluminum capacitors
http://www.nichicon.com

Kemet Corp.
KEMET is a manufacturer of solid tantalum, multi-layer ceramic and aluminum organic capacitors.
http://www.kemet.com/

Visual Elements: Tantalum
Discovery, uses, physical information, and key isotopes.
http://www.chemsoc.org/viselements/pages/tantalum.html

ChemicalElements.com: Tantalum
Basic information, atomic structure, and isotopes.
http://www.chemicalelements.com/elements/ta.html

H.C. Starck Inc.
Mo, Nb, Re, Ta, W Powders and their compounds, boron, borides, carbides, nitrides, AMPERIT®-Thermal Spray Powders, alloys, composites and parts. Functional Polymers: Anti-static and High Conductive Coating, OLED, Capacitor, Electroluminescence. Engineered ceramic parts made of Al2O3, BN, BC, SiC, Si3N4, ZrO2.
http://www.hcstarck.com/