Adobe Acrobat offers the Preflight options to save a PDF document to the PDF Archive standard (PDF/A), and to validate that the document complies with that PDF/A standard. Open a PDF document you want to convert to PDF/A and select:
Adobe PDF Library higher support conversions to the PDF/A-1b format using the PDFProcessor plug-in, though this plug in is not available on all platforms. This feature is demonstrated in the PDFAConverter sample program.
Datalogics also offers the pdfaPilot product provided by callas Software. You can use Adobe Acrobat if you want to create a PDF document that is from PDF/A compliant based on a PostScript input file. To programmatically generate PDF/A compliant files from PostScript documents, consider the PDF Converter product, also offered by Datalogics.