sign up forms introductory email

Hello

I have just created a sign up form and linked it to my website. Does anyone know if there is a way to auto-generate a welcome/inital email after someone signs up? 

What is the best system to use with Constant Contact for creating click funnels?

Many thanks for any advice given ....I'm a very non-tech person on a steep learning curve at the mo!

Best wishes

Sara