josh,
If the record source for your report is a table, or a query with
no criteria, then you will get everything.
Depending on how you launch your report there are several
methods to define which records to print.
You can use the Search option here and look for "RunReport"
(without the quotes) and you should see some samples.
You can also base the report on a query with a criteria based
on a form control.
You can also look in Northwind and other sample dbs.
Wayne