Inkscape is an opensource similar to Corel Draw and Illustrator, the difference is Inkscape totally free. Even Inkscape have no many great tools compare to Illustrator, there are many trick to create 3D effect.
Here the list, some of tutorials creating 3D effect image using Inkscape.
Most common software to create vector image is Adobe Illustrator, Macromedia Freehand, Corel Draw. Infact, Inkscape, an opensource/ freeware can do this great thing too. Here’s vector image created using Inkscape.
Only using shape, shade, and coloring, results detailed vector. Bjork Vector is created by Dzofar , graphic designer from Indonesia. He admire Bjork so much 
The interface of Inkscape is user friendly specially for newbie. List of button at vertical left toolbar are quick easy navigation. Its symbol represent its function. There’s Shape Tools 
including square, 3D box, circle, star, swirl. This tools easy to use to create a shape. To scale or select we can use this Select Tools 
. Beside using Shape Tools, we also can use these calligraphy pen, path , and pencil to create freehand image 
.
Quoted from official Inkscape site “An Open Source vector graphics editor, with capabilities similar to Illustrator, CorelDraw, or Xara X, using the W3C standard Scalable Vector Graphics (SVG) file format.
Inkscape supports many advanced SVG features (markers, clones, alpha blending, etc.) and great care is taken in designing a streamlined interface. It is very easy to edit nodes, perform complex path operations, trace bitmaps and much more. We also aim to maintain a thriving user and developer community by using open, community-oriented development. “
