This is the book that a friend gave me, which started this whole endeavour. She was given it by another friend of mine and they both have benefited from it. You can get it on amazon.com and amazon.co.uk. 

But you can also visit this website for an overview: http://www.breakingtheviciouscycle.info.

On this page, you can find a fairly comprehensive list of foods you can and can't eat listed alphabetically: http://www.breakingtheviciouscycle.info/legal/listing.

Foods you can have are called "legal." Foods that you can't are "illegal." Fairly self-explanatory.

When in doubt, you can google: "SCD (insert food here)" e.g. SCD pistachios, and most foods will automatically pop up like this:

There are also a plethora of blogs, facebook groups, and websites. I will add ones that I find useful here with time. 

WARNING: Most blogs and recipes posted online are done so by non-professionals. And in our first week alone, I found many cases of recipes including illegal ingredients under the name SCD. So always double check your ingredients before embarking on a new recipe.