MS Office 2007 includes the ability to "publish" a document or worksheet in 
either PDF or XLS Paper Specification (XPS) format from an Excel or Word 
object.

#define wdExportFormatPDF        17
#define wdExportFormatXPS        18

#define OptimizeForOnScreen        1
#define OptimizeForPrint                0     higher quality, bigger file

oDoc:ExportAsFixedFormat( filename, nExportFormat, lOpenAfterExport, 
nOptimizeFor )

There are more optional parameters which let you export only a portion or 
range of you source, keep various editing markers in place, and so forth.