The following websites contain reliable information on meteorites, asteroids, comets, and the missions sent to study them.
NASA: Asteroids, Comets & Meteors Overview
SolarViews: Meteoroids and Meteorites
SolarViews: Asteroids
SolarViews: Comets
Mission websites:
NASA Center for Near-Earth Object Studies (CNEOS)
Dawn Mission: Vesta and Ceres
ESA Rosetta Mission
NASA OSIRIS-REx / OSIRIS-APEX Mission
JAXA Hayabusa2 Mission (Ryugu Sample Return)
NASA Lucy Mission (Trojan Asteroids)
NASA Psyche Mission (Metallic Asteroid 16 Psyche)
NASA New Horizons (Pluto and Arrokoth)
Additional resources:
IAU Minor Planet Center
JPL Solar System Dynamics Database
NASA Solar System Exploration Portal
cosmiCave.org 