I must have got unlucky with the online trading as I only really ever found people looking for stupid things, like a level 100 Celebi.
This is probably like the fifth time I have said this in this thread but if you are searching the GTS you are doing it wrong.
The right way to use the GTS is put up a Pokemon for the Pokemon you want. If you put up a fair Pokemon for it (Usually a starter or version exclusive) then your trade will complete itself in a few days.
If you actually search the GTS you are only ever going to see the trades that never go through and stay there forever.