Buying Lonely Planet books in Bangkok

Hi,

I'm moving to Bangkok very soon, and I'm planning on buying several Lonely Planet books (Bangkok, Thailand, Diving in Thailand etc).

But I'm not sure if I should by them before I leave home, or if they would be cheaper to buy when I'm actually IN Bangkok? I bought some LP books in Bali last year, and they were heaps more expensive than at home - but I guess that might be because it was quite a touristy area. However, I also bought some in Singapore which I think was more expensive than buying them online at lonelyplanet.com.

Does anyone know what the prices on LP books are if you walk in to a bookstore and buy them in Bangkok? Or can you buy them online on a Thai website and have them delivered to your Bangkok address? For example the Lonely Planet Bangkok? Or LP Thailand?

Cheers,

Sabrina