DIY freestanding dog gate with very detailed instructions. Easily customizable to the size of your furry baby and the door opening you are trying to enclose. Could use any type of wood or paint it to match your decor. From http://www.thisoldhouse.com on "How to Build a Dog Gate".
The wrought iron motif of the hand railing is repeated in this custom wood and iron gate. Designing a gate might take awhile with all the hand forged metal art and decorative parts, balusters, and panels available. This is similar to how I'm doing mine to match oak & iron.