There are a lot learing resources for IRT(Item Response Theory). But the most useful onese are those fit you well.
Here is a list which helped me a lot.
Books:
The Basics of Item Response Theory: Frank B. Baker: 9781886047037: Amazon.com: Books-link
Item Response Theory: Parameter Estimation Techniques, Second Edition (Statistics: A Series of Textbooks and Monographs): Frank B. Baker, Seock-Ho Kim: 9780824758257: Amazon.com: Books link
Vedios:
A Conceptual Introduction to Item Response - YouTube
Pdf Documents:
A visual guide to item response theory VisualIRT.pdf
IRT mini-tutorial interactive
The Basics of Item Response Theory (by Frank Baker)
Slides:
IRT - Item response Theory
基于项目反映理论_宋慧鹏
Websites:
Item Response Theory GOOD
Item Response Theory cas.usf.edu
Softwares:
SSI - Scientific Software International, Inc.
WinGen: Windows software that Generates IRT parameters and item responses
