There are four or five big plugins on the form building front. Visual Form Builder Pro is made by Matthew Muro, who lives in my home state. His plugin is pretty slick, and is on the lower end of the price scale.
He just released Visual Form Builder Pro 3.0, and it comes with some pretty nice improvements. He also launched a redesign of his site.
I use and love Gravity Forms. But not every plugin is for everyone. If you’re looking for alternatives, keep VFBPro in your back pocket. Chris Lema’s comparison post from mid last year is also a great resource.