Where can I find information on Isaac Bignell, and how much his
original painted prints are worth?

Here are a listing of two Isaac Bignell profiles I found through
google:
http://www.canadianartprints.com/artistbioAB.html
http://www.canadianarttreasures.com/bio_ib.html

Isaac Bignell was a self taught Cree painter born in Manitoba, Canada.
He was born in 1958 and died at the height of his career at the age of
just 37.

His works reflected his culture and included a deep respect for the
spirit and power of nature. Here is a quote from Isaac
(http://www.canadianartprints.com/artistbioAB.html) regarding his
works:
"My art is strongly influenced by the traditional ways of my people. I
was brought up to live off the land from an early age. Hunting and
trapping, living in harmony with the earth has taught me to respect
the animals and the spirit and power of nature.
I hoop dance and sing Pow Wows to maintain my cultural heritage.
Through art and dancing I attempt to influence native people to
continue their cultural ways; the gift that was given to us by the
Great Spirit."

Isaac became known for the flowing lines of his wildlife imagery and
developed a unique style of sponge painting.

Here is a site which provides scans of three of his paintings which
happen to be for sale:
http://www.wholesaleimpressions.com/wholesale_020.htm

They are each listed for $630.00 in US currency. All three are acrylic
on paper paintings and were created betwen 1984 and 1986. The sizes of
the paintings vary in range and the largest is 13"w x 20"h. You may
wish to contact this company to get an accurate estimate of one of his
paintings if that is your intention. The name of the company is
Wholesale Impressions. Their email address is
support@wholesaleimpressions.com and the phone number is 204-228-1254.
I hope this was of some value to you.