出国以后如何在国外购买机票？

You can always book flight via airline's own website, that is usually the best and least expensive. Most hotels have business offices that you can use their computers for free and printing.

1 用WIFI 上网 + 一张VISA的信用卡2 找当地旅行社，一般的酒店都可以代订的3 打

有wifi的地方再订呗，现在出去基本都有wifi覆盖，而且一般也能找到当地的旅行社代订。

国内信用卡上有visa就可以用啊

只要需要国际双币卡。