In Access 2000 and later, you can set the Seed of an AutoNumber field
directly with ADOX code.
This example is a bit more than you need. It loops through all your
TableDefs, to automatically reset the Seed where it is below the maximum
used:
http://allenbrowne.com/ser-40.html
If you wish to raise the value, you can import a record that assigns a value
to the AutoNumber field. Example:
http://allenbrowne.com/ser-26.html
To lower the Seed after deleting records, just compact the database.