Prince Lestat is supposedly a stand-alone book in the series and can be considered an AU. It’s very cracky and the characterization is inconsistent with the rest of the series.

My short answer is SKIP IT FOR NOW. Read #1-#4, those are SO MUCH BETTER. Then some of the later ones, like The Vampire Armand, Blood and Gold, and Pandora… after all that, you can go back to Prince Lestat and consider it a fanfic AU. Much less painful that way, less VC reputation-tarnishing that way ;]