When I first got started in electronics, just getting started was a lot more expensive. Just programming a chip would require a 50$+ dollar USB programmer, and Arduino was still a very new project.
A few years after this I heard about eBay as a source of cheap parts, and everything had changed! You could get Arduino clones and breakout board on the cheap at the cost of long shipping times. Those clones many not be as reliable as brand-name items, but for a programmer with a limited budget looking to experiment they were a godsend.
Suppliers such as Mouser or Digikey are still the best options for quality individual components and fast shipping. On the other hand, for breakout boards, enclosures and other small specialized parts there are many places where you can do your shopping.
Here is a list of the most common ones:
Slightly more expensive than some of the other options. It has a lot of good breakout boards and development kits, but I like them even better for tools, cables and other odds and ends that are bigger and harder to ship. The speed is also hard to beat if you need something RIGHT now.
Adafruit and Sparkfun
Those shops are the most expensive in the list: instead of just sourcing cheap parts like most shops, they create and document the parts well and have many projects using them. It’s not exactly cheap and you’ll pay for that documentation and support, but quality is top-notch and they’ll readily replace broken parts.
eBay used to be THE place to shop, but you can now often find the same parts for cheaper on AliExpress or Banggood. It features many sellers so the shipping speed and quality of the descriptions and service will vary depending on the shop. I usually shop for fixed price items so I can get them right away instead of waiting for auction items.
It’s the cheapest way to get parts directly from China. You have to know what you’re looking for or be willing to experiment and dig a bit since the descriptions are generally not very good. They are many similar parts from different sellers.
Like eBay, there are many sellers on the site of varying quality and shipping speed so your experience will vary. You will also end up receiving your order in many packages if you order from different sellers. It can be a bit frustrating to see your order tickling in slowly until you’re just missing one part or two to get started. It’s also a bit annoying that you can’t use Paypal to pay.
Also a store from China, but it’s one huge store and everything ships for their few warehouses. You’ll receive one or two packages and have only one way to contact support instead of many sellers. Checkout is really quick and you can use Paypal to pay.
Many items can also ship from the US, so you’ll get them faster if that’s your location. AliExpress sellers sometime have US warehouses, but it’s a lot rarer.
The descriptions are not a lot better than on eBay or AliExpress, but you don’t need to sort through too many parts to find what you want. It’s still a great choice if you don’t mind paying a tiny bit more for the convenience and are looking for the cheap stuff.