Yes, both GoToWebinar and Proof offer a Free Trial.
GoToWebinar is designed for Freelancers, Large Enterprises, Medium Business and Small Business.
Proof is designed for Medium Business and Small Business.
Pricing for GoToWebinar Starts at $49/User/Month whereas for Proof Starts at $26/Month when Billed Yearly.
Some top alternatives to GoToWebinar includes Zoho Meeting, ON24, EasyWebinar, ClickMeeting, LiveWebinar, ezTalks Webinar, Zoom Video Webinar, WebinarNinja, WebinarJam and eWebinar.
Some top alternatives to Proof includes and undefined.