Q: I need my application to perform better. Do you know any good resources on .NET performance?
A: I know one great resource. The resource is the "Improving .NET Application Performance and Scalability" book from Microsoft's Patterns and Practices group (or whatever their name is this quarter). You can read the book online, download the PDF, or buy the 1152 page paperback.
The book includes chapters dedicated to manage code performance, ASP.NET performance, and ADO.NET performance, among others. There guide also include How To articles and checklists you can use for reviews. It's an oldie but a goodie.