You don't mention whether your copy is an original or reproduction and obviously the latter is going to be worth much less.
If you are unsure with your painting is a copy, you can check on the official Robert Wood website robertwood.net/how_to_tell_reproduction.
A good quality large framed reproduction Robert Wood painting could be sold at a minimum price of $20.00, although eBay carries some Wood reproductions on sale for $50.00. Of course, this doesn't mean necessarily mean they'll get any bids.
The auction site primetimeauctions.hibid.com appears to have sold the original 'October Gold' by Robert Wood earlier in 2014, with the painting fetching a price of $65.00. This is likely a copy, so unless you own the original, this would be a rough value of your painting.
If you own the original, well, originals of Wood sell for four and five figure sums on eBay, around $5000 to $20000, but you will need to have your painting authenticated first if you intend to sell.
You could discuss the possible value of your painting at dart.fine-art.com, an online art community with several threads dedicated to Robert Wood. askart.com/AskART/artists/bulletin is a similar site you could try.
Check out other Blurtit answers to questions about Robert Wood by reading What Is A Original Signed Robert Wood Painting Worth? or What Would A Signed Autumn Leaves 1959 Painting By Robert Wood Be Worth?