First, take a pass at grouping your excel fields into logical groups. This is will be used to build your tables in access. You'll want to list for each column in your spreadsheet:
field_name
data_type (string / numeric / date / currency)
Once you do that, you'll want to normalize your data...
http://www.datamodel.org/NormalizationRules.html
Now you are ready to build your access database. If you want to restrict access, add a table called users with the following fields:
userId (primary key - incremented)
name
pw
group
status
Even if you have one user now, you may have more later and it only takes a few minutes.
Next steps depend on what languages your environment supports...ASP, PHP, ColdFusion, Java, Perl, etc.