Hi Sue,
It depends what you mean by "database". Usually it's fairly simple to
move the data from Excel worksheets to Access tables, but anything else
- searching, sorting, reporting, validation... - has to be re-created
using Access's tools.
In general, start by creating a new Access database, then import the
data from the Excel workbook. Often, an Excel "database" benefits from
being split into two or more related tables in Access; see "About
designing a database" in Help - and there's a Table Analyzer tool that
can help with the process.