Actually, good luck. It's difficult to find anyone with a Ditto FS, since your FC determines your FS. You'd have to get lucky for it to be Normal, then be lucky to even have the Ditto in it. In all the 100 people on my main 3DS and 60something in my secondary 3DS, I don't have a single person with a Ditto FS. And folks who did have Ditto FS's were so swamped with FC requests, think a lot of them stopped shortly after anyway.
You know what you could do though? Trade Scatterbug on GTS for Ditto. At this point though, I imagine you'd need to have very difficult things to gather them. But in beginning, before I started breeding the Monsoon/Sandstorm/Snow(? can't remember) I was putting up my regular Scatters for Ditto. Didn't state what kind they were just threw them up and they'd trade away pretty quickly. Got enough pretty quickly that I sorted out the three Ditto I'd need (and used initially) to breed with. Each had a + IV in something other didn't have, 2 each. It also helped me obtain Ditto with different natures for breeding as well.
Can't say what is good trade bait on GTS anymore for Ditto, but might be worth a try.