There’s a nice thread here that goes more in depth about PCH scams, it’s worth the read if you are interested.
As for travel scams, the most common is shady travel agencies that impersonate major airlines, sometimes other more well-known travel agencies, to mislead others to their site and/or helpline. Usually they are found through Google SEO tricks to appear higher up, or through deceptive Google result ads, or they are found through spam bots that flood anywhere they are able to post. The usual scam goes that people will search up an airlines support line, get mislead into calling the impersonators, booking and then booking the ticket through them. Whether or not they get the ticket varies on who they end up calling. Some do provide the ticket at a fair third-party price, some offer discounts, others will call up later demanding more money as there are “problems”, some will give the ticket for the wrong seat, while others will just not provide a legitimate ticket.