Several of the standard Sites templates include embedded Forms.
When your Site was created using a template, any embedded Google Spreadsheets, Documents and Spreadsheet Forms were also copied to your account. If you are the site creator, you can find these newly-created assets in your Documents listing.
Each Form has an associated Spreadsheet that will collect that form's data.
To adjust the Form:1. To find out the name of the form, edit the page.
2. Find the spreadsheet and note the title.
To be notified of any form submissions, open the relevant spreadsheet, click on Tools>Notification rules.
You can find out a lot more about using forms here