Sent them some Bitcoins four days ago, and received a pending confirmation right away. Then nothing…
A day ago emailed them, and received no reply.
Now what? Keep waiting or write it off as bad experience and book somewhere else?
I think recently there is a growing trend in the number of websites that were active in the past becoming inactive/obsolete. For example pizzaforcoins used to be a really big thing in the bitcoin circles but now is defunct.
I would bet that travelforcoins is something similar. It is likely to be an abandoned project.
You should have checked out their social media, and whether they have any sort of recent activity before just blindly using their service.
What you can do now? Not much, maybe try to go onto whois and find out some more info about the owner and contact him personally. If you can't, then tough luck. But keep trying, you deserve to have your money back.