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ASP.NET and ASP Developers
Professional ADO.NetProfessional ADO.Net by Julian Skinner
Buy used from: £0.01
A good place to start for ADO.NET
ASP.NET UnleashedASP.NET Unleashed by Stephen Walther
Buy used from: £0.03
A decent ASP.NET book, even if it's all in VB.
ASP .NET Step by StepASP .NET Step by Step by Microsoft Press
Buy used from: £0.54
A good guide for creating web.config files and basic ASP.NET
Dynamic HTML: The Definitive Reference: A Comprehensive Resource for HTML, CSS, DOM & JavaScriptDynamic HTML: The Definitive Reference: A Comprehensive Resource for HTML, CSS, DOM & JavaScript by Danny Goodman
Buy new: £38.25 / Used from: £2.40
Never be without this book. It's the best HTML reference I've ever seen.
JavaScript: The Definitive Guide (Definitive Guides)JavaScript: The Definitive Guide (Definitive Guides) by David Flanagan
Buy used from: £3.88
And this it's javascript counterpart.
ASP in a Nutshell: A Desktop Quick Reference (Nutshell Handbook)ASP in a Nutshell: A Desktop Quick Reference (Nutshell Handbook) by A.Keyton Weissinger
Buy used from: £0.01
A very low cost ASP book and a decent reference.
Professional Ado Rds Programming with AspProfessional Ado Rds Programming with Asp by Matt Brown
Buy used from: £1.21
And for ASP development, a decent ADO reference.
C# in a Nutshell (In a Nutshell (O'Reilly))C# in a Nutshell (In a Nutshell (O'Reilly)) by Peter Drayton
Buy used from: £2.75
A good language reference for C#
XSLT Programmer's Reference 2nd EditionXSLT Programmer's Reference 2nd Edition by Michael Kay
Buy used from: £4.99
A reasonable reference.
JavaScript Programmer's Reference (Programmer to programmer)JavaScript Programmer's Reference (Programmer to programmer) by Cliff Wootton
Buy used from: £0.99
A good book if you need to know what works in various browsers. Goes well with the O'Reilly book.