A lot of travel companies started offering online booking at the advent of the internet. That is most especially true for travel agencies, and hotel chains. And there are also who went into the industry as middle-men with the likes of Expedia, Travelocity and Hotels-Search-Engine.org. They buy in bulk from hotels and airlines and sell them at rates affordable for the average consumer. The good thing about them is that they can take care of your itinerary. You can book your airline with them at the same time book your hotel room and even rent a car.  

If you will visit their website, you will find lots of advice and recommendations for your vacation. It would also be wise to visit sites that offer travel tips such as Tripadvisor and Lonely Planet.

If you’re particular about a certain country that you want to visit, you can also check out Wikipedia. They have extensive data about various subjects including countries and even not so known cities and towns. It’s better to research about the country that you’re suppose to visit than head straight there without knowing anything about the country. The internet is the best source for that.