you give him a drink
The thirsty man is at the gate between Canalave city and route 218
well you can get 1 in route 218 from a fisher man
In Pokemon Diamond/Pearl, you find a old man at route 212 with a Leafeon.
On route 218 when you battle a trainer. the man with blonde hair who is a guitarist
You can't catch a Phione on Pokemon Pearl. But you can receive one.Get a Manaphy (Pokemon Ranger series or Pokemon Event)Get a Ditto (Route 218 using PokeRadar)Put them in the Daycare (Sandgem Town)Get the egg they make (talk to the man outside the Daycare looking east)Hatch the egg (bring a Magcargo along it'll be faster)
you can get one from some Pokemon and from a man you don't battle talk to him he will give you a dawn stone
no man gives you a happiny platinum only in diamond and Pearl
You have to defeat team galactia in mt cornet and then the man guarding the route to sunnyshore goes.
The Odd Keystone is given to you by a man on route 208
In Pokemon Diamond and Pearl you will have to go to route 228 and talk to an old man, I think you might have to do the same in Platinum.
go down to the man in fighting clothes he doesen't whant to battle talk to him
a drink from the vending machine on the 5th floor of the dept store in veilstone city (it's to the upper left of the city from the pokecenter)