As New York Small Business Law blog says, "Articles on choice of business entity are a dime a dozen."  But I agree this article concerning Choice of Entity from the worldwide law firm of O’Melveney & Myers is an excellent guide. 

The article contains the answers to many of the frequently asked questions concerning using a "C" corporation, an "S" corporation or an LLC/Partnership for business operations.   The article discusses the tax aspects of the various entities.  The tax treatment of your business should be a major factor in determining which business entity you choose.  I also recommend speaking with your accountant before you make a decision on which entity to use.