The ribbon syndicate and your villa which you cn buy items for
In the Desert Resort somewhere
No.
you have to find all the Pokemon then talk to the guys blocking the resort area
in the servile area
At the resort area
You can get a syther above the Resort Area. there will be a patch of grass above the Resort Area.(You have to have a pokeradar)
The Resort Area is located on an island on North Sinnoh off of route 229. There are not Poke-Marts in the Resort area or battle gyms.
get to resort area
The Resort Area
Your villa is in the resort area
In The Resort Area
the best Pokemon is a lv100 magikarp