Asian foodshops? Or you can make it fairly easily. Most recipe books with Indian or Asian recipes in have a recipe for paneer. It usually involves heating milk, adding a souring agent (like lemon juice) and letting the curds and whey settle and cool. You can then tip the whole thing into a suspended cloth and let it drip until all the whey has come out. Then you just cut it into blocks. It usually works best if you drip it overnight, though, so you can't just make it on a whim, you have to plan a bit.