You can find two; one in Hotel Cyllage, another in Lumiose City.
Bulbapedia
As for tips, here is a very basic IV breeding guide for Gen VI (includes some swearing as well). Basically, IV breeding in X&Y means you have to pile on the IVs and keep breeding for more 'superior' offspring, meaning you can keep passing on more 31 IVs to the offspring, rather than the more luck based version in Gen V and previous. You also need to catch a lot of Dittos.
