Of course you can often find short bios by entering an artist’s name in a search engine and these can work fine if you examine them carefully. In general, the biographies posted by major museums, art galleries, and artists themselves, are of a higher quality than those provided by the many commercial sites such as Artcyclopedia, AskArt, Artnet, etc. Accuracy varies. Web bios for historic figures are frequently copied from public domain (pre-1923) sources. Wikipedia entries also vary, so check the “Talk” tab where the quality of the article may be discussed.
Art Writers:
Curators, Educators, Gallerists, Critics, etc.
These are annual publications. Check several relevant years.