I've recently had an opportunity to read Microsoft ACE Team's ... book "Performance Testing Microsoft .NET Web Applications" and would highly suggest this book to anyone who is looking to find performance bugs or increase performance on your teams web applications. The book is well written, gives real world examples, explains the most common bottlenecks in different areas and how to detect them (disks, network, web tier, sql tier, etc) and has a great section on how TCA works. ... I highly recommend this book.