Have you ever heard of a plant called Stephanandra? Neither had I, until I found it in a little reference book I have, for leaf identification. I often use my little book of leaf line drawings as inspiration and design reference. I do not plagiarise the drawings. I do not trace, scan, or even re-draw the designs. I do use the designs as references for my own leaf drawings, so that I get a shape that is at least based off the original leaf form.
I find that in using reference pictures, it is very important to do your own freehand sketches, several of them. Then you are definitely getting your own perspective on the topic, rather than a copy of the reference material. Then be sure to work from your sketches, rather than the original reference picture.
I based this new bronze chasing, a stephanandra leaf brooch, off a design I found in the book.

Here is a close-up, so you can see how I obsessively texture the surfaces with my little chasing tools.
I originally thought it was a variety of oak or even a maple variety. I did a google image search for stephanandra later and found a wide variety of garden shrubs, with really great leaf shapes, perfect for jewelry and ornamental ironwork. The most frilly stephanandra leaf shapes are quite reminiscent of some of the traditional stylized acanthus leaf forms.
For the full details on this brooch, go to http://www.etsy.com/view_listing.php?listing_id=21046977, and to see a few others, go to the brooch section at http://www.etsy.com/shop.php?user_id=20486§ion_id=5127286 .
Oh, I almost forgot!
Go check out these hydraulic press forging videos by Randy McDaniel of Dragonfly Forge.
You'll be able to see what it is, how it works, some tooling for it and what it can do.
Just click on these links:
Part 1 : http://www.youtube.com/watch?v=pl_A4mRGFZk
Part 2 : http://www.youtube.com/watch?v=sW2G-zxTwKs
Randy is a great guy, a talented blacksmith, and also a great source for lasercutting. He'll even prep your files, which means a lot to someone like myself who has no desire to learn CAD.