It all depends on what you want to do, and how you want to do it. Beginning ASP.NET 3.5 covers accessing databases in chapters 11 through 14. It uses concepts like LINQ and the built-in web controls for data access.
The book Professional ASP.NET 3.5 digs deeper into "manual data access" using objects like Connections, DataReaders and DataSets.
You can also check out the ADO.NET quick starts:
Some of the guides may seem outdated, but most of the concepts still apply. For example, to access a database and get some data out, check out the SqlDataReader example:
There's a lot more information available, but it's difficult to give you precise pointers as I don't know what exactly you are looking for.
My book (and the Pro edition) is a good starting point to get familiar with the general concepts. Google and these forums would then your next step to get detailed answers to detailed questions.
Hope this helps; if not: please let me know.
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Author of Beginning ASP.NET 3.5 : in C# and VB
, ASP.NET 2.0 Instant Results
and Dreamweaver MX 2004
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