Everything you would need should be located on the following pages. There will be snippets located on most of these pages to display how to execute each task. I've only pasted the fine-grain arcobjects approaches below. You can substitute some of this work to the related geoprocessing tools if needed.
Connecting to geodatabases and databases
Querying geodatabase tables
Converting and transferring data
Thanks for the direction and links, I was hoping for a general outline or example to start, but this helps. I do have a question regarding versions of ArcGIS. I am looing to build a console application exe that will do some nightly extraction > conversation GeoDB to SHP the SDE version is 10.0 can I still build the solution with the 10.2 SDK?
You would need to build the console application against the client that we be used to connect to the database. If you're using SDE 10.0 I would think that this would mean your client would need to be Desktop or Engine 10.0 or higher.
I don't know your particular business requirements, but if you're focused on data extraction it may be easier to write a python script to accomplish this task and run it as a scheduled task. The ArcObjects code shouldn't be too difficult to write based on the information you've provided so far. I would think that if I had to write this I would spend the bulk of my time on the joining data portion.