I get a lot of my parts from Sparkfun Electronics. For the most part, they carry almost everything I need when it comes to components and sensors. Aside from the website telling me I don’t accept cookies when I do, I find it pretty easy to use their website.
The photos can be misleading; not that they mean to be. It’s hard to realize that the 3 inch photo of a board represents a board that’s 1 inch by 1 and a half inches. The miniaturization can be startling. But the photos they provide are excellent and clearly show the components, whatever they are, up close and personal. Quite often, the clarity of the photos will turn on a light bulb of understanding me I didn’t get from reading the text alone.
They ship with the cutest red boxes you ever saw. Little tiny ones about 2 inches on a side and an inch deep right up to twice the size of a cigar box and many steps in between. They use “extruded cardboard” as their packing material. I assume this is a nod to recycling and biodegradabity, but the stuff works great. Also, you can pick it up as a single knot —try that with foam peanuts. They could be a little more descriptive on their packaging. When I order a number of very similar items it can be difficult to differentiate between them. They separate the different items well enough, it’s marking them as what they are that could use some improvement. If you buy a selection of chips, get out the magnifier and get ready to read the chip markings to tell who is who.
But from an Arduino to a joystick shield, to a motor shield, ethernet shield, ultrasonic range sensor, infrared sensors, temerature, illumination, gas and fire detection, humidity, video devices, breakout boards, hook up wire, tools, and even books. They have LEDs, capacitors, resistors, ICs, transistors, breadboards, protoyping boards, and on and on and on. Aw, what the hey, here’s a copy of their catalog.
As a general, all around go-to site for components, Sparkfun is always a first stop.