Trust me when I tell you, there is no other software better than Zbrush that will allow you to create a model like this. Zbrush also has THE BEST decimation capability of any software I’ve seen and you can output in STL format if you’re planning on doing CNC or rapid prototyping.
As for making an exact duplicate of what’s shown in the image, including an exact duplicate of the specialized texture, that would take a master Zbrush artist to do that because of the specialized knowledge needed to recreate that texture exactly as shown. Thing is though, almost everyone here is a master Zbrush artist and I wouldn’t be surprised if someone hasn’t already contacted you! =D
If you just need a basic gator tail though, you could probably learn to do that yourself with Zbrush in about 3 days of learning. Or you might even find what you need already made on a site like Turbosquid, which is a site where 3D artist sell their 3D art.
As for good videos for learning Zbrush, well Pixilogic, the makers of Zbrush have already put out a great set of videos for learning Zbrush and they are free to view. Just go to to this link and start learning:
http://www.pixologic.com/zclassroom/homeroom/
Also check Google as there are hundreds of free video tutorials that can be found all over the web covering all aspects of Zbrush.
Of course, answering your question as asked, there are a few commercial video distributes for learning Zbrush that are out there too. Off the top of my head I can think of Lynda and Gnomon as being two. As for good, I wouldn’t know because I’ve always just accessed the free video tutorials that are out there.
All the best!
PS- I just took another look at your image and would like to add that it is a rendering of a 3D model. So if you track down where the image came from, you may be able to track down the artist who created the model and make a purchased directly from the artist. And I wouldn’t be surprised if the model was created with Zbrush and if so, the actual artist might come across your thread and contact you about your wish to purchase the model! HAHAHA! =D