What types of artwork should one attempt using oil pastels as a beginner?
You can check out the section on oil pastels at my art lesson site http://www.explore-drawing-and-painting.com. I am still adding more info unto that section but you will get some idea. The techniques and tools are listed there. If you are new to oil pastels, I suggest you would try painting a very simple still life lit with one single light source. Unlike other mediums, oil pastels are not forgiving as they get muddy easily if you are not careful. So try some still life first. Fruits, or solid simple objects. Practice a lot. Work from dark tones to light tones. Preferably keep the colors separately according to their tones(values). Clean your hands and pastels with towel or alcohol swaps constantly. Hope this answer your question.