Legality of Art Sale

I don't know what you mean by a printed work that a card from a popular card game, or how you know that the original artist worked on commission. A specialized card that's part of a board game with other elements could be copyrightable. The orginal artist, if he created the card as a "work for hire" would not own the original card, the employer would, and if there's a protectible copyright, then only the rightsholder has the exclusive right to create "derivative works" from the original.

You're best off seeing an IP lawyer to fully disclose what orginal work and what altered work you're referring to so you can get specific advice.

Disclaimer: Please note that this answer does not constitute legal advice, and should not be relied on, since each state has different laws, each situation is fact specific, and it is impossible to evaluate a legal problem without a comprehensive consultation and review of all the facts and documents at issue. This answer does not create an attorney-client relationship.

"Found" art? What is that?

Seriously, you need to see an intellectual property attorney to discuss whether or not what you want to do infringes on anyone's copyright or other rights.

Query: Alright, so I have a printed work, in this case a card from a popular card game and I take paint and brushes to it and alter it to make it my own. Is it legal for me to sell the card in its new state?

Answer: Maybe. You've taken Work A and modified it to be Work B. If the public would recognize in Work B the underlying Work A then you've likely infringed the "derivative right" copyright in Work A (assuming copyright attaches to the work). In short, only the owner of the copyright in Work A can make other works based on Work A. There are, however, many exceptions to that rule. This is, therefore, no short answer to your question. A copyright attorney would have to evaluate both Works.

Query: If so, does the original artist who worked on comission, his employer, or I hold the copyright to that art? In otherwords, is it found art?

Answer: Like my colleagues, I don't have a good grasp of what you're talking about and so will leave these matters alone.