I created a survey form and sent the link out and people filled out the form, but I did not include a space for their contact info.

I received forms back. How can I find out who sent the forms back. I did not put a section for their name and email on that form.

Unfortunately, there is no way to figure out the name an email of the person that fill in the form. If you have the phone number, you can contact that person so he can give you the proper information and resubmit the form.

The only solution would be to track the device he used and try to contact that person using the IP. This also is not great as many user can us public devices to submit a form.