The Form Block gives you a fast way to make forms. All data collected by the form can be accessed at Dashboard > Logs > Form Submissions.
Customize your form
The Add tab allows you to add questions
This question is required forces people to enter SOMETHING before hitting submit. Don't forget to use the Add Questions button, the Add button adds the whole form to your page.
Edit tab allows you to change your questions or the order they are presented in. You can change the order with the up and down arrows.
Preview tab allows you to see how the form with look.
The Options tab adds contains some additional choices:
Form name is used in the reporting section of your dashboard.
Message to display shows up above the form after it is successfully submitted.
Notify me by email lets you send the form data to an email address when submitted.
CAPTCHA is the annoying "what does this word say" trick that is used to keep spammers at bay.
Redirect to another page lets you send users to a new page after submitting. If you want more control over the thank you message this is a great way to go. You could also build a "fill out this form to get access to our..." type deal with this.
Add uploaded files to a set allows you to, like its namesake, add files uploaded through the form to a file set. This allows you to easily keep track of files uploaded through the forms in the file manager.
You can see all the results of your forms in the Dashboard. Just type "form" into intelligent search.