There are actually quite a few. Drizzt has his group of friends (very unbalanced though, not a spellcaster among them!), and the Prism Pentad books (Verdant Passage in particular) have almost a classic D&D party. Thinking of others - the Moonshae trilogy has a party, and others that also have a really tight PC-group type arrangement off the top of my head are Azure Bonds, King Pinch, the Cleric Quintet...
Novel parties tend to split up more than PC parties though, just for dramatic tension.
What is very rare in D&D novels is point-of-view, game-accurate spellcasters. Low-level spellcasters, not the uber can-do-anything-offhandedly people like Elminster or the Simbul or Azalin or Hamanu or later-books Raistlin. Spellcasters who ponder what spells to prepare that day, or who worry about whether they should use their one daily third level slot to fireball the gnolls or save it for later, etc etc.