Ryan,
I'm in a similar position. I took the DEV 401 training class and
still have to get my DEV 401 certification. I'm looking to obtain a
SF Dev position in 2013 but I'm not working in SF in my current
position.
I've read the following book, which gives a nice intro into both APEX
and VisualForce (Development with the Force.com Platform: Building
Business Applications in the Cloud):
http://www.amazon.com/gp/product/0321767357/ref=pd_1ctyhuc__bxgy_01_01
If your looking for a book on writing good code in general, I found
the following book to be usefull (Clean Code: A Handbook of Agile
Software Craftsmanship):
http://www.amazon.com/gp/product/B001GSTOAM/ref=kinw_myk_ro_title
Good Luck !
Eoin