The biggest thing for me with grokking LINQ was understanding the difference between IQueryable and IEnumerable types of operations. Most of the complexity in t

The biggest thing for me with grokking LINQ was understanding the difference between IQueryable and IEnumerable types of operations. Most of the complexity in the runtime with it is with IQueryable. I don't know if there are a lot more resources out there but the best one for me was understanding Expressions and that namespace in .Net and trying to grok the ASTs that were being passed around to understand how it was all working. There are a couple smaller LINQ implementations out there like Linq to Amazon that you can take a look at (Linq2<insert whatever here> libraries seemed to be coming out of nowhere for a while).