<p>I know that there has been a couple questions about tutorials on moq. But I am wondering if there are any sample apps out there that use moq in the context of an n-tier business application using ado.net.</p>

<p>I find the tutes good, but they don't seem to bring everything all together into the big picture. Thus, I am looking for a sample app that brings the full picture together.</p>

<p>Also, I think there is a little bit of a lack of examples which specifically deal with mocking and testing the logic in the data access layer.</p>

<p>Cheers 
Anthony</p>

Moq, like all unit testing frameworks, should not have much a concept of n-tier-ness about it.
One would typically use unit testing to test each individual class one-at-a-time. When a particular class is a little more complex and relies on having references to component classes and calling methods on these component classes, one might use a mocking framework such as Moq to create these constituent components, and to have the class-under-test use these mocked components instead of the real deals.
It looks like you are looking for how to use Moq in integration testing, where you bring all the components together and test the whole shebang all at once, including the data-access components. For doing whole-shebang tests, typically you need the real components, not mocked versions of them.