While you cannot download the entire book, Google Books often provides a preview of 20-30% of D.S. Hira’s System Simulation . This is excellent for checking specific tables (e.g., the Kolmogorov-Smirnov critical values) or chapter introductions.
If you are looking for specific chapters, or need help with a particular simulation problem,
Hira introduces the foundational concepts, distinguishing between continuous and discrete systems. He explains the steps involved in a simulation study, from problem formulation to implementing the results. 2. Modeling Complex Systems