Reddit reviews All That Is in God: Evangelical Theology and the Challenge of Classical Christian Theism

These sources will be more philosophical and less exegetical. After learning the philosophical concepts, I've laid them up against scripture as I've read and I've found that the classical stuff answers more questions and leaves less unanswered than any other system I've run across so far.

• The One and the Many - W. Norris Clarke for a primer on classical metaphysics. That will help for terms such as "essence," "form," etc.
  
• All that is in God - James Dolezal will help put some of the pieces together once you get comfortable with the main terms used. He's a bit grumpy, but his points are good.
  
• Augustine's De Trinitate in whatever good translation you can find.
  
• Retrieving Eternal Generation ed. Sanders and Swain for the relations between the persons.
  
• Constant re-reading of the creeds of the church.