要说地道的回答的话,建议你看看Family Album U.S.A.（走遍美国）的讲解版.
在episode1,act2,有对于thank you的地道回答的讲解.
它上面讲的我记得有这些：
最基本的,you're welcome.
My pleasure.
Anytime.
No problem.
Forget about it.
比较地道比较美国的：
1.It's nothing/Nothing.
2.You bet.
3.Sure.
可以看看Family Album U.S.A.
其实对thank you的回答有很多,也要结合语境.
比方说美国人会说No worries,
但是英国人会说cheers mate或者直接就是cheers.
对女孩子的话,还可以说At your service.
另外,LS说的you owe me,意思是“你欠我一个人情”,是一个玩笑话,对好朋友说的.给个例子给你：
—Thank you so much for driving out here to pick me up so late at night.
—No problem.But you owe me one.