Depending upon where you live, you may have a plethora of sources for ethnic ingredients available or not. It may be necessary to order items online or rely on people who are travelling to bring back special spices, etc. You may find, for example, that black lentils are not in your grocery store but are available online. However, with just a little more research you may find them tucked away in one or more local small ethnic groceries that most towns have. These shops may be stand alone or frequently can be housed in one corner of a restaurant serving that type of cuisine. I’ve been shopping for years at a little market which is in a corner of an Indian restaurant close to where I live. There are others, often tucked away and unless you know the restaurant or search online, you may not know about these little places.
The Indian market close to me has many ingredients that cross cuisines, so I wind up shopping for quite a few staples there. The rice is far better quality than grocery store rice, no matter the brand. There are many more brands and types of rice at this little store than at a grocery. I talk with the people who work there to find out what brands are most popular and/or the highest quality. A variety of lentils are available, as well as many hard to find spices and sauces. I especially like the produce at this little market, as the long, thin eggplant, fresh ginger root and hot peppers are far fresher and higher quality than what I can find in any of the grocery stores in the area, not to mention cheaper. Substantially so. It is wise to ask when their produce is delivered as there will be more variety if you shop the day of or day after the delivery.
By going there with one of my friends, I also learned that not all of the produce may be out on display. She asked the owner for some sort of vegetable and he brought it out from the back. I started using that as well, as I often need only a small amount of cilantro, not a giant bunch.
It’s well worth doing a computer search to find out what is available. I live in a medium sized city in the Southeast US and within 25 miles of me there are something like nine Asian groceries, more than twenty Mexican tiendas, fifteen to twenty Middle Eastern/Mediterranean markets, and several others. Who knew? So, do a search before you automatically assume you have to place an online order. You may just be able to find your ingredients locally and support local business in the process.