N-Tier Applications and Table Adapter
I have been searching for a solid link to a full explaination of N-tier applications on .NET 2.0 . I came across a nice article that not only reviews this topic but the Table Adapter also. You can add a dataSet and then use the Table Adapter as a level of abstraction. The Table Adapter allows for multiple queries to be run against it not to mention for the defining of your own methods. There is also a wizard that makes the process of creating a TA easy as possible.