SQL Database mapping and other data retrieval sources

I have an engineering application developed in c# and I need the following component/tool.

My application for each of its calculation cycles should read a set of parameters as input. Some of the potential customers keep those input parameters in excel files, others in sql databases and others in forms (paper or digital) or even other not known yet.

So, for each deployment, I need to customize the "input reader" module to comply with a specific requirement and at best I may be able to reuse some code. I need a module like an sql mapper tool to be integrated in my application so I will be able to construct a specification set (using eg. sql or QBE) to gather data from sources like sql, excel files or other and map them to my own internal dataset for the input parameters.

Thanks in advance for your time and support.

Regards, semag