I own a couple watercolors by Allan Brook and George Miksch Sutton. How can I find out their market value ?
Sell them
Take them to an auction house (or Antiques Roadshow) and get them appraised for insurance purposes.
Assuming you mean Allan Brooks (not Brook), Google’s cache of this page says one particular watercolor had an estimate of $2000 - $3000.
Note, until you have the actual painting looked at be a real expert, all bets as to values are meaningless.
I meant Allan Brooks.
The snag is that I live on the western side of the Pond, and I doubt anybody overhere knows Brooks.
Thanks everyone.
Sorry, I meant eastern side
You might consider contacting the Sam Noble Oklahoma Museum of Natural History on George Miksch Sutton. They’ve got 120 Suttons on display there.
Regardless of where you live, auction houses (Sotheby’s or Christie’s, for example) are a good place to start. The links tell you what information is required. Estimates are, apparently, free.