牛津字典 / 朗文字典買幾錢?

Hello!
Is a pleasure for me to answer this question!!

First,I recommand
Oxford English Dictionary For Schools(OE)+
Concise Oxford English Dictionary(OES) to you.
Price:
OE:$325(It worth!!)
OES:$130(commercial press)
Second, I will recommand
<<朗文當代高級辭典>> to you
Price:
$428(commercial press)
I will also recommand <collin cobuild dictionary>,since it's very useful.
Sorry for can't provide the price of the dictionary!

---428 (OE)
-325
-=103.