I can't speak for everyone, but I paid for most of my samples. A great starting point is ebay. I don't know about shipping to your country however. Try to find stores in your country that have an ebay store. To help with shipping costs, it's not usually ecomonical to just get one sample. Sometimes certain ones can be had cheap though. Some sellers have bulk sample auctions that let you get an assortment of samples for about $2 each. However, I don't know your countries shipping costs, so it's hard to say.
For niche samples, try luckyscent.com. Gendarme.com sells samples of their products at a reasonable price. Who knows, maybe you'll befriend a basenoter and he can send you some homemade decants!