Where should I start if I want to learn how to cook great Indian food?
Start with a decent anglicized Indian cookbook. Some examples are Madhur Jaffrey's Indian Cooking, Betty Crocker's Indian Home Cooking by Raghavan Iyer, Pat Chapman's Taste of the Raj. These cookbooks have been written with the non-Indian novice in mind. After you have some experience, you can move to more traditional and regional cookbooks: Summers Under the Tamarind Tree, Prashad: Cooking with the Indian Masters, My Bombay Kitchen, La Porte des Indes, The Kerala Kitchen, Julie Sahni's Classic Indian Cooking, etc.
After reading the cookbook of choice, select some simple recipes. Put together a list of ingredients. Particularly necessary spices, fresh and dry, and dals. If you are lucky enough to have an Indian grocer with 20 miles or so, start there. Their prices will usually be the best and the spices and dals the freshest. Otherwise check out the local ethnic markets. Last resort, go online. Do not buy in bulk.
You can now start cooking. Do your Mise en Place so you aren't distracted by prep when cooking. Follow the recipe exactly. You may cut down on the number of chilies or substitute milder ones, but do not eliminate them entirely. Watch your cooking temperature, many dishes need a long slow cooking time for the flavors to come together.
Learning and mastering how to cook Indian food can seem like an overwhelming task. However, making yourself familiar with the various Indian spices is really the first step to take you on your way to cooking Indian food.
There are many websites that describe various Indian spices and their uses. I've listed some websites below for your reference:
Once you are familiar with the various Indian spices, you will want to research some Indian recipes. Here are some websites to refer to:
Finally, make your grocery list of spices and fresh ingredients based on the dishes you decide to make. The spices can be sourced both at your local Indian grocery store, Trader Joe's/Whole Foods or even Amazon.
Good luck and Happy Cooking!