I got this recipe originally from a former co-worker of mine who spent a few years in Thailand researching for her dissertation. She brought some of this along to a potluck and promptly had to email everyone copies of the recipe. I had put off trying to make it for 2 years because I thought it was exotic and difficult. Turns out that's not the case at all. Thank goodness.
Now, I'm lucky because the grocery store across the street from my apartment carries a pretty solid selection of ethnic foods, of all varieties. So getting my hands on red curry paste, coconut milk, and kaffir lime leaves was pretty easy. I would have to imagine that large enough grocery stores (or even Whole Foods), would carry a selection if you don't have an Asian market near you. Although, with online groceries now, it shouldn't be that difficult at all. Even Amazon has a selection: Coconut Milk, Mae Ploy Red Curry Paste, and Dried Kaffir Lime Leaves. I'm still on the hunt for fresh lime leaves and basil, which I'm sure would only help, the dried varieties do just fine in a pinch.
One of the most beautiful parts of this recipe is that you can customize it just about any way you want. Have chicken on hand instead of shrimp? Not a problem! Want to add some veggies for crunch? Not a problem! Don't like your curry too spicy? Not a problem! Actually, about the spiciness, some curry pastes are more potent than others. I would recommend tasting your curry before you put in the shrimp to see how it is. I added a fair amount of cayenne and red pepper to mine, because I like my curries to clear my sinuses. And I didn't even get it that spicy. I was also using Thai Kitchen brand red curry paste. As long as you taste as you go, you will have a curry that will suit your own preferences. Next time I make it, I will definitely kick up the heat a little more and probably throw in some garlic and peas as well.