Online electronic stores are usually the safest bet when ordering spare parts, as long as you can wait a day or two for shipping. These stores run out of large warehouses which brings savings in three ways: 1) There's a low overhead because there's no store front to run or extra salespeople to pay; 2) they reach a larger consumer base, so they purchase in bulk, lowering the purchase price; 3) the warehouse space is capable of holding lots of stock, so they run out of items less frequently. Clearly, when it comes to savings, purchasing online is probably the best choice. All you have to do is buy the item and within a day or two it will be on your front step. It doesn't get any easier than that.
As we can see from this comparison, each store has some pros and cons. Local stores can't offer the best prices and may be out of stock, but if you need an item right away, they are the only option. eBay can offer incomparable deals, but still doesn't offer the security of a store. The online electronic supplies store can offer great deals, will have items in stock, and is a trusted shopping source. If you don't need emergency electronic parts and can wait for the item to be shipped, online electronics stores are the best way to shop for spare electronic parts.