One of the comments I get asked by friends, acquaintances, commenters on this blog, and so on, is ‘do you have any ideas for what products to import?'. My answer is, of course, “Yes, I have an entire spreadsheet full of potential products, and no, I won't share”. Even if I was more benevolent, the chances are my little Excel spreadsheet would be of no use to the vast majority of people as it relates to one or two specific niches that most people care nothing about (nor have any desire to care anything about!). So that right there is the key to finding successful products to import: you have to have a niche or two that you are an expert in.
One of the examples I routinely mention of a product to import is horse saddles. I know almost nothing about horse riding except I know that I am not alone in knowing almost nothing about horse riding. By virtue of that fact, that means someone who does know something about horse riding eliminates their competition drastically (I sure as hell won't ever be their competition!). For the iPhone case importer, they will compete against almost any other potential importer who has ever had a great idea to import iPhone cases (and trust me- a lot of people have had that idea!).
Aside from eliminating your competition by concentrating on a niche, you also also have the opportunity to offer a lot more value to your customers. Because I am an expert in my niche, I often find myself looking at existing products and thinking of how to make them better, even in the slightest way. I might find good complementary products to couple with the products or I might improve the documentation included with the item. In a couple of strokes of engineering genius, I've even been able to suggest different materials for some components to increase quality. These are things I can only do because I know the products I import, inside and out.
One of the other benefits of focusing on a niche opposed to a mass market product is that the suppliers for these products will be on the smaller side. Such suppliers are normally open to smaller orders and you can actually become a client who matters to them. The number of suppliers will also be smaller, so it makes picking a supplier a lot less overwhelming. Aside from that, Scammers would rarely think to target horse saddle buyers in some Western Union money scam.
If you're not an expert in a particular niche, you can likely become one in a short time. Visiting brick and mortar stores that either specialize in a niche you're interested in or at least sell certain items in that niche is a great way to start. Magazines specializing in that niche give a lot of information regarding products in that niche and also contain advertisements which let you scope out your competition quickly.
Ultimately, if you're able to become an expert in the products you're importing, your customers will be happy and your bank account will be too.