I need a few for remembering some moves I need. It would be nice to know where they all are.
I just wanted to add but also on route 104 near the cottage (in the sandy part) if you use your dowsing machine near that area, you should find a heart scale. I hope I helped! (Even though it wasn't much)
There are 3 main ways:
Use Thief/ Covet on Luvdiscs
According to Serebii, Luvdisc appear on Route 118, in Victory Road and Evergrande City. Best to use a Super Rod on Route 118 and you get 60% encounter rate.