For as far as I can remember there are only like 3 major bookstores in the Philippines. The oldest and most well-known is National Bookstore. The main and biggest branch before was in Cubao, Quezon City (Now known the Gateway City). It had 4 floors I think. It carried all the major text books/reference books you needed in school. Plus of course the books you may want to purchase just for reading. The 2nd most oldest was Goodwill Bookstore. i think the main branch was from Manila but there is also 1 big branch in Gateway, I am just not sure if it is still there. Haven't visited the Philippines for the past 6 years.

Goodwill Bookstore carries text books too but not as many titles as National Bookstore. And last but not the least Power Books. They started branching out in the late 1990's and their forte is like Barnes and Nobles or Borders. You can sit and lounge around and read books all day long. They don't particularly emphasize in text books; they are more on regular reading material.

However, some may not know that there are a lot of second hand bookstorea around Recto, Manila. Which specializes in trading text books/ reference books for students. If you have time to look for the books you need in a very low price this is where you would go. It is just like amazon.com but these are real stores. You can barter, buy or sell your books there for a very minimal cost.

Imagine if you wanted to buy Harry Potter and the Deathly Hallows in hard cover you have to pay 1,200 pesos in Power Books. But if you go to Recto, you might be able to buy it for 600 pesos. (Exchange rate is $1 =48 pesos).

Hope this helps.