ScholarSpace, the UHM Institutional Repository uses Dublin Core Metadata, a standard that facilitates discoverability of files stored in ScholarSpace.
The Digital Curation Centre in Edinburgh has a template in Word format to use to develop a data managment plan. See http://www.dcc.ac.uk/sites/default/files/documents/tools/dmpOnline/DMP_template_v1.2_100106.doc
DCC also has a work-in-progress data curation manual at http://www.dcc.ac.uk/resources/curation-reference-manual. A chapter on metadata at http://www.dcc.ac.uk/sites/default/files/documents/resource/curation-manual/chapters/metadata/metadata.pdf may be helpful in developing descriptive information about your data sets for optimal usability and discoverability.
The world of social science data curation has been shaped by the collaborative efforts begun in 1962 of the Inter-university Consortium for Political and Social Research, housed at the University of Michigan. At http://www.icpsr.umich.edu/files/ICPSR/access/dataprep.pdf there is a 47 page guide to preparing data for archiving. Best practices for dataset preparation are applicable to all disciplines.
The Data Documentation Initiative is another international collaboration that was created to support the sharing of social sciences datasets. See Data Archiving and Networked Services (DANS) for a list of best practices in documenting data collections.
Oak Ridge National Laboratory Distributed Active Archive Center for Biogeochemical Dynamics (ORNL DAAC) has links to guidelines and introductions to naming and metadata for geosciences and GIS.
Inter-University Consortium for Political and Social Research (ICPSR) has links to information about file naming, metadata, etc. that will be useful to all data managers. The site provides good information on planning and organizing data files before the start of a project.