As the artist, I retain the copyright to all artwork produced. You will own the artwork, but I maintain ownership of the copyright. For example, if you bought a DVD, it would be illegal to copy and sell this DVD.
Any new works reproduced from my artwork (i.e. reproducing a painting as a card, prints, posters, on a t-shirt, etc.) would be a violation of copyright law.
Should you be interested in such reproductions, please contact me for permission.