It's shockingly easy to find where a pureblood lives in the wizarding world, what with all the wards and arrogance they have no problems broadcasting the exact locations of their ancestral homes to the world in Wizengamot records that are public domain. Naturally, since Hogwarts is the hub that most little pureblood princes and princesses go through Wizengamot records and legislation are freely available for even a first-year to glance through. Eventually, I found the location of my first target, Goyle Manor, situated in a nice remote location just off the coast of Wales. I'm in the money now.