Stone pipes from the native american mounds (along the Mississippi river) in America have been found which have carvings of what definitely look like depictions of elephants on them.
http://www.kentuckygenealogy.org/christian/mound_builders.htm
However, no archaeologist would ever try giving a 10,000 year old dating to any mound. They'd be laughed off their feet. Datings show two time periods for the mounds... Around the year 1500 AD for some (Cortez' journals talked of there being chiefs living on top of mounds) and around 600 AD. Certainly not 10,000 years ago.
There is also a mound that was a quite good depiction of a mammoth.
There is also an incised stone called the 'Lenape Stone' (many like to call it a fake, but good fakes generally weren't made in 1872. Poor fackes were made back then, because they weren't trying to fool very high-level people at the time) purportedly discovered in Bucks County, Pennsylvania between 1872. If genuine, it would be the first artifact that depicts american indians attacking a mammoth.
http://abob.libs.uga.edu/bobk/lstone_a.html
http://abob.libs.uga.edu/bobk/lstone_b.html
http://www.webroots.org/library/usanativ/lstiatm0.html
and, another interesting page on it...
http://www.spanishhill.com/Susquehannocks/How_they_lived.htm
Supposedly, all mammoth were extinguised 10,000 years before (some scientists say they might have continued until 8000 BC).
Some believe it is possible that a few straggler mammoth's continued in America until as little time ago as 1500 AD.