Free JavaScripts provided
by The JavaScript Source
To build the form needs only a couple of steps. However, I noticed that client need to click on a link to return main page. That's not really recommend. They also bring user to the site that took time to load.
It took a lot of step to build a form, it may get annoying. However, user will be direct back to our site after they fill it, which is a good thing to me.
This site is highly recommended apart from the two above. Apart from sending user directly back to our site after filling up the form, it also has anti-spam option. This is necessary to avoid unsolicited emails.