Attached Link: http://3dmodelworld.com/lightmodels.asp

Sorry, I didn't mean to imply that you could just pop in a picture and get a 3D object. You can do flat or symmetrical objects like the butterfly you mentioned. Since this object is in profile you will have a hard time making the nose higher than the tail without hand editing the entire height map. Once you do this you will be unable to rotate the deer or use any other camera angle. This is because the legs and head won't be undercut and will be solid all the way to the back. The 2D picture method is best if you want the background to show through around this deer. The attached image is from the free reindeer model at Lannie's 3D modelworld it is in lightwave with textures but cannot be posed in different positions. There is also a deer for sale at DAZ that requires poser to open and position. If you really want to model a deer you can use several terrains, lattices, and metaballs to draw the antlers, head, neck, body, legs, etc. then rotate and stick them together. There are several people who are very good at this(I'm not)who can help more than I can.