Acroname. Good source for sensors.
http://www.acroname.com/

All Electronics: New and used electronic kits and equipment.
http://www.allelectronics.com/

Allied Devices
http://www.allieddevices.com

Allied Electronics: good source Test & Measurement, Interconnect, Enclosure Products, Tooling
http://www.alliedelec.com/

American Design Components
http://www.adc-ast.com/

American Science and Surplus: fun gizmos and surplus, mechanical components and science kits.
http://www.sciplus.com/

Atbatteries: Batteries of all kinds. Wide selection and great service
http://www.atbatt.com

Arrick Robotics
http://www.robotics.com/

BCD Electro
http://www.bcdelectro.com/

Best Hong Kong: Great prices on LEDs
http://www.besthongkong.com

BG Micro
http://www.bgmicro.com/

Cana Kit: Electronic kits and pre-assembled modules
http://canakit.com/

Centerpointe Electronics, Inc.: Electronic parts, kits, and test equipment
http://www.cpcares.com

C&H Sales: good source for surplus motors, solenoids, power supplies and parts
http://www.aaaim.com/CandH/

Chaney Electronics: Electronic kits
http://www.chaneyelectronics.com

DATAKITS : Electronic kits
http://kitsrus.com/

DigiKey Corp. Integrated circuits, LEDs, sensors, tools.
http://www.digikey.com/

Edlie Electronics
http://www.edlieelectronics.com/

Edmund Scientific: Optics galore and other instruments associated with optics
http://www.scientificsonline.com/

Electronic Goldmine
http://www.goldmine-elec.com/

Electronics 123: Electronic parts and kits
http://shopping.netsuite.com/electronics123

Elenco Electronics: Electronic kits and tools
http://www.elenco.com

Fry's Electronics
http://www.outpost.com

Gibson Tech Ed. Inc.: Electronic kits for educators
http://www.gibsonteched.net

Graymark: robotic kits
http://www.graymarkint.com/

Haltex Electronics. Integrated circuits, LEDs, sensors, tools.
http://www.worldwidewire.com/

Herbach and Rademan Co.
http://www.herbach.com/

HobbyTron: Consumer electronics, electronic parts, kits, and test equipment.
http://www.hobbytron.net

Hosfelt Electronics: Electronic equipment, kits, high-intensity LEDs
http://www.hosfelt.com/

International Microelectronics
http://www.imaps.org/

ISD Inc: Single Chip Voice Message Systems
2841 Junction Avenue, Suite 204, San Jose, Ca 95134
800/825-4473
408/428-1422
Fax 408/428-1422

Jameco Electronics: highly recommended supplier, as the pictures are most informative to the beginning artists/inventor
http://www.jameco.com/

JDR Microdevices
http://www.jdr.com/

Kelvin Electronics: Electronic parts
http://www.kelvin.com/

Lite Source Inc: Replacement lamps of all sorts, specialty lamps
http://www.litesourceinc.com/

Lumex: Optics and electro-optical components
http://www.lumex.com/

Marlin P. Jones & Association Inc.
http://www.mpja.com/

MCM Electronics. Integrated circuits, LEDs, sensors, tools.
http://www.i-mcm.com

McMaster-Carr Supply Company
http://www.mcmaster.com/

MECI (Medelson Electronics Co. Inc) an amazing place to browse floor after floor of surplus parts, massive surplus parts a must visit-in-person location
http://www.meci.com/

MondoTronics, Inc.: great source for muscle wire.
http://www.mondotronics.com

Mouser Electronics, Inc.
http://www.mouser.com/

Newark Electronics
http://www.newark.com/

Nordex
http://www.nordex.com/

Optek Technology, Inc.: Optics and electro-optical components
http://www.optekinc.com/

Parallax Inc
http://www.parallax.com/

Photonics Inc.: Optics and electro-optical components
http://www.photonics.com/

PIC Design
http://www.pic-design.com/

PowrUps Corp.
http://www.powrupscorp.com/

Quality Kits: Electronic kits
http://www.qkits.com

Radio Shack: quick source of pricey parts without added costs of shipping
Google your hometown and the name Radio Shack to find local store
http://www.radioshack.com/

Ramsey Electronics
http://www.ramseyelectronics.com/

The Second Source: Replacement lamps of all sorts, specialty lamps
http://www.thesecondsource.com

Seitz Corporation
http://www.seitzcorp.com/

Servo Systems
http://www.servosystems.com/

Smart Electronics Ltd.: Electronic kits (located in Athens, Greece)
http://www.smartkit.com

Techniks, Inc.: Transfer Film for etched circuit boards, microcontrollers, and timers.
www.techniks.com

Trost Modelcraft Hobbies: radio controllers, servomotors, and Cyano-acrylate glue
3129 W. 47th St., Chicago, IL
773/927-1400
(no website)

Velleman: Electronic kits and products, test equipment
http://www.vellemanusa.com