Its a  very nice thing that blogger has a new contact form gadget that can be installed in any blogger blog.
before this, many, used to adopt contact from from Google docs.
but the thing is something simpler than anything, user enter a valid name, valid email, and subject text to form and when submit, it send to to owner of blog  without loading the page.
if you have not already installed blogger contact form gadget in your blog, its time to add that, here is how you can add blogger contact form gadget to your blog.

So, after installing the new blogger contact form for blogger, you can customize the appearance of contact form with css.

Here is a simple css Snippet that change the appearance of the Blogget contact form.

#ContactForm1_contact-form-name {} //Style Input field where use have to enter name
#ContactForm1_contact-form-email {} //Style Input field where use have to enter e-mail
#ContactForm1_contact-form-email-message {}  //Style TextArea field where use have to enter e-mail message.
#ContactForm1_contact-form-submit {} //Style submit button of the form


Example (Which i have used in my blog)

#ContactForm1_contact-form-name {border: 1px solid #6B0C23;border-top: 1px solid #350E0E;}
#ContactForm1_contact-form-email {border: 1px solid #6B0C23;  border-top: 1px solid #350E0E;}
#ContactForm1_contact-form-email-message {border: 1px solid #6B0C23;  border-top: 1px solid #350E0E;}
#ContactForm1_contact-form-submit:active,#ContactForm1_contact-form-submit:focus:active,#ContactForm1_contact-form-submit.focus.active {-webkit-box-shadow: none;  -moz-box-shadow: inset 0 1px 2px rgba(0,0,0,.3);box-shadow: none;}
#ContactForm1_contact-form-submit {background: transparent url(https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiDFNC0Sr_xXjcdRgGYYZEgUuW_KmFKumWwp65nhqqVXy2owuvuqlwpRiZjyoU3Nnvb0O3pV5Aprv6mvYwDB5o8AbVbUi9dvFvWopWwQ5yP6f0g4YW7a1Kx413XOstZ4fP_uYIwul_kMn8F/s1600/footer_button.png) no-repeat scroll -2px 0;  height: 42px;  width: 97px;  border: 0px transparent;  color: white;  margin: 0px auto;}
#ContactForm1_contact-form-submit:hover {-webkit-box-shadow: none;box-shadow: none;}





Now, a blogger can add contact form widget in blogger blogspot blog,within seconds ! that too come with a good styling and also customization possible with css.
Blogger's new contact form is a nice, simple and fast one.
There are many ,who uses google docs to create contact form
I have tried many contact forms already, but this one worth to add it. because we can trust Google.

If a user enter a valid Name , email address and Fill the subject message in to the form, owner of blog will receive an email to their email account which they have created the blog with.

Lets see how to add this contact form to your blog.

Go to blogger dashboard - > Layout/page elements, and click on add a gadget. it will popup a window of gadgets that you can install.
in More Gadgets tab, you can see a gadget named Contact form for  blogger.
Click to add.

Save This , drag the gadget to any section you want it to appear.

So, here you are, for adding a recent posts widget in your blogger blogspot.