For an exhaustive source of Spurgeon material, see the Spurgeon Archive. What I've included here are just a few of my favorites.

• Lectures to my Students VOL 1  620k  azw3  epub  mobi
  
• Lectures to my Students VOL 2  620k  azw3  epub  mobi
• Lectures to my Students VOL 3  550k  azw3  epub  mobi
• Lectures to my Students VOL 4  660k  azw3  epub  mobi

• Feeding Sheep or Amusing Goats?  17k  (still true!)
• Immutability of God  180k
• Soul-Winner 625k (modernized)  azw3  epub  mobi
• The Greatest Fight in the World 295k (modernized/annotated)  azw3  epub  mobi