How do i buy apps on my LG quantum?

I just bought my LG quantum, and every time i go to an app's info page to buy it, two buttons come up.. "install" and "share" i click install and then there are two buttons that say "Buy" and "Cancel" but the buy button isnt highlighted so i cant click it... and then a white box comes up telling me the info couldnt be found and to check back later.. any help??