What type of stein do you have?
Can you post a picture? use flicker or photobucket.
Do you know the manufacturer?
Beer Steins vary in price depending on their composition like glass, porcelain or puter, Maker, pattern and colors. Without seeing the stein, it would be impossible to give you an exact amount on value. I will give you this link to use a comparison site to get an idea of what your stein may be valued at: http://www.steincenter.com/stein/pc/viewCategories.asp?pageStyle=h&ProdSort=0&idCategory=55&page=2
This site has many different steins to help you find your value. Joan