Distributors
Or, how to buy stuff (which is sometimes surprisingly hard if you don't want 10,000).
Local (to Atlanta, GA USA)
If you need parts on short notice, look at these. You can also order online from these distributors.
Ack Radio SupplyMcMaster-Carr
Large mechanical supplier. Also has industrial electrical parts. Has will-call so
you can call in an order and pick it up in a couple of hours. This is the place to get mechanical
parts in Atlanta quickly.
Surplus electronics
Almost everything here is cheap. This is definitely the way to buy LCDs. These are usually the cheapest places to buy very common or very unusual parts.
All Electronics CorpB.G. Micro
The Electronic Goldmine
Development, prototyping, and special-purpose hardware
AcronameRobot-related parts: Sensors, microcontrollers, small motor drivers, etc.
Digilent
Programmable logic development boards. Lots of them, with add-on boards, and they're cheap.
Spark Fun
Lots of robotics and general prototyping stuff. Breakout boards for various interesting chips and
some parts that are hard to get through other channels.
Online distributors that sell small quantities
Digi-KeyLook here first. Good online parametric search.
Mouser
Look here second. Similar to Digi-Key, but somewhat different prices and inventory.
ArrowAvnet
Arrow and Avnet are large industrial suppliers that sell many parts in small quantities.
Jameco
Electronics distributor. Not as large as Digi-Key, but sometimes cheaper, and often easier to
find common parts (they don't have dozens of kinds of resistors).
Mechanical parts:SDP-SI
MSC
Online Metals