iText# (iTextSharp) is a port of the iText open source java library written entirely in C# for the .NET platform. iText# is a library that allows you to generate PDF files on the fly. It is implemented as an assembly.
http://sourceforge.net/projects/itextsharp/
http://www.cnblogs.com/zhuor/archive/2005/12/31/308908.html
http://www.cnblogs.com/EKPK/archive/2009/06/04/1495867.html