Here, you will get the list of topics in Web API. I have collected a limited set of Web API tutorial.
There could be more on Web API, but I have written only about those topics for which I have done an implementation or demonstration.
Introduction to Web API
Web API is the Microsoft open source technology for developing REST services based on HTTP protocol. ASP.Net Web API is a framework for building, consuming HTTP based service. The advantage of Web API is that it can be consumed by a wide range of clients like a web browser and mobile applications.
ASP.Net Web API Tutorial
Other Blog Series -