You could probably use a find button, that brings up a small modal window to enter find criteria, then a button to close that window and perform the find. You could enter the find criteria in a global field that's either free form, or attached to a value list if you want to limit the types of things users can search
Option 1, you can use a different layout based on the same table occurrence to perform the find, then change layouts to your report layout.
Option 2, enter search criteria into some global fields--possibly in a popover, or in a small modal window opened for the purpose. Then a script performs the find, sorts your records and changes to your summary report layout.
For examples of such scripted finds, see: Scripted Find Examples
Thank you both, I think I know what to do now.