Probably one of the best things to get you started is what I used.  The ATGen SDK.  You just give it a table and it generates a full functional but completely empty module. 

You can then go look at how the admin controls, DAL and business logic are created without all the other surounding stuff that makes something like say the events module.  It's very usful.  Another good thing is once you get the hang of things you can use it to help create your real modules.

I can't remember the link to it right off but look for posts from Crispy.  He a core team member that wrote it and it's linked in his signature.

Cheers,