What causes shading artifacts and how to eliminate them? I've been getting these shading inconsistencies with sub surf mod regardless of the subdivisions value, and "Smooth Vertex" deforms my shape undesirably. how do I go about fixing this? 
 

This is how it looks in Edit mode:
Seems like your topology is the culprit. Subdivison modifier tends to not work well with triangles like the ones you have. Try using only quads (squares). 
Other than that, I think your normals are flipped. Try this: Hit "T" to bring up the left hand panel on the viewport. Then go into EDIT mode and find the "Shading/UVs" tab. There scroll down and click "Flip Direction".
Hope this helps.