To identify Trichoderma sps on morphological basis, it's difficult task. I think, book on Trichoderma written by Nagmani and C. Manoharachari. Osmania University, Hyderabad.
The recent book by Samuels and Hebbar (2015) is excellent. A slightly older work, using the teleomorph taxonomy of Hypocrea, that can be helpful is in the Studies in Mycology series, https://www.sciencedirect.com/journal/studies-in-mycology/vol/56/suppl/C.