Here are my search ideas:
Internet resources (ignoring the obvious, like Google):
The major site for professional galleries is: www.artnet.com
. simply type in the artist name in the search box. If the artist is shown by an existing gallery it will pop up. Or if there are past auction results it will let you know. You will have to pay for the auction results, but the rest is free.
Artinfo.com: new but catching up to artnet.com
Wwar.com (world wide art resource). More clumsy but also useful.
Wikipedia.com Is useful, but short on artist bios.www.artcyclopedia.com
Good but limited as well.