It depends.
For example, type "Time", or any other such common word, in Amazon. You will find there is more than one book with that exact title. Certainly, when searching for books, I have found many books with the exact same title. In such cases, I use the author or genre to narrow down my search.
On the other hand, if the book is in the same genre, then it would matter, although again, maybe not so much.
In your case, since you say it is a different market, I would say don't worry about it. And in any case, the publisher might change the book's name anyway, because they feel they can market it better with a different name. If they feel the title duplication is a concern, they'll change the title.
So I would say go ahead and use the title, and let the publisher worry about any name clashes.
Edit: In view of @One Monkey's comment below; if the title is similar to another book, make sure it is not similar to one by a best selling author, or a famous series. So if you choose The Hobbit, or Rendezvous with Rama, you will be in trouble.