Just tried browsing the app store direct from my own iPad3, as I tend to mostly browse the store from my PC, but it seems fine here, infact I put the same search details in that you used, and I had the relevant apps show for me to take my pick from..
I must admit this does seem a strange one.. does all other browsing appear ok, IOW I assume this issue is only with the app store? I think your've already tried a non-destructive reset/reboot by holding down the on/off switch and the Home button at the same time, without much joy, if your the same user I was reading about yesterday with this problem. I notice you said you had re-installed too, so as suggested, it does sound like you may have done something to restrict access on the app store, I can't really think what else it can be... other than a setting that's been overlooked somewhere, either on the app store account settings or the ipad itself.
Can you access and view your app store account okay with no problems from another device .. like your PC or Laptop ?
When you do hopefully find the solution, can you let us know what was causing it.