Brand new from a shop....or from an individual? If from a shop, then they should be able to get a warranty card for it unless they are not an authorized BT dealer.
I bought my Hoyt target bow from an unauthorized dealer w/no warranty, but I really liked the look/feel of that bow and it was a fair price. So I guess the bottom line is......if you're happy w/the $$ you save, then make the purchase. Just make sure you really look the bow over for flaws or damaged areas, cause if you buy it and then find damage......who are you gonna turn to?
JMO,
Greg