Sorry that I'm a bit rushed right now or I would write a fragment that might help you. But here is the gist of it.
1. Write a parameter query for which the date is the parameter. Read the HELP files on parameter queries. Be sure to read the examples of using parameter queries with VBA code.
2. Create your search button using the Command Button wizard and tell it to open the query. The query you will open is the one you write in step 1 above. That's why you created the query first.
3. Now go back into the button_click event code that the wizard built for you. There will be a part where the wizard built in a DoCmd OpenQuery for you. In front of that code, you need to insert an Input Box to demand and accept the date. Read the HELP files on Input Box. What you'll get back is a string that contains whatever was input. To treat this as a date, enclose the date string in # (on either side, as #1-Jan-2003#) and store this as the parameter for your parameter query.
4. Now recompile and save the code.
That should do the trick for you.