One of the more frustrating aspects of Android for non-US users is that a lot of the content on the Google Play Store (formerly the Android Market) isn't available in other countries. Certain apps and usually all of Google Music, Movies and Books aren't available in all territories. Users have been voicing their complaints at the Google Play Google+ page, and Google has responded. Essentially, they're trying as hard as they can, but the intricacies of international content licensing are not for the faint of heart.
Here are the Google Play representative's words:
We're working hard to bring the different types of media in Google Play to more countries, so that more of you can take advantage of the tools and deals we offer. There are many aspects to launching a feature like this internationally that take time to get right and mean more than just flipping on a switch. We'll be announcing more availability for books, movies, and music as each rolls out, so stay tuned on this page in the coming months!
Negotiating licensing even in the same country is notoriously difficult. Getting digital deals for books, movies and music can sometimes take years, and many pieces of professional content have different publishers in different countries. While Google is certainly trying, it's probably going to take quite a while for Music, Movies and Books to roll out on a country-by-country basis. Other digital distributors like Apple and Amazon have had the same issues, but they've got several years' head start.
However, if you're waiting for a particular app to be available in your country, it might be best to take the direct approach. Look up the developer on the Google Plus Store, then send them an email; odds are pretty good that they want to get as much exposure as possible, especially if they're independent. More established and entrenched content like the BBC iPlayer or HBO Go is obviously not negotiable this way, but you'd be surprised how often a developer is genuinely excited to hear from users, or in this case, potential users.