Yes.
Evee to Vaporeon
You can't find vaporeon you need to use a water stone on an Evee to make it become Vaporeon.
Ditto transforms back after a battle. So, no.
this is the answer for dimond and pearl ONLY flareon=use a fire stone jolteon=use a thunder stone vaporeon=use a water stone espeon=level her/him up in the day with high happiness umbreon=level him/her up in the day with high happiness leafeon=level it up near the stone with moss on in the forest(near the corner) glaceon=level it up near the stone with ice on on the very blizzard route close to snowpoint city(in the top right corner)
give it the water stone.
ditto, female eevee, flareon, jolteon, or vaporeon
actually you can to do so get the evee that's in the game evolve it to jolteon or flareon or vaporeon then put it in the four island day care with a ditto then hatch the egg you get and its evee.
Evee to Vaporeon
Use a water stone.
If you have an evee evolve it to either flareon or vaporeon or jolteon or espeon or umbreon or leafeon or glacieon. Either way when its evolved put it in the daycare with a ditto then wait awhile and you when you come back you can receive an egg and when it hatches it evee.
Evee + Ditto in daycare
Actually you can breed a Vaporeon with a Ditto. It will just take some time for an Egg to come out.
Either Jolteon, Vaporeon depending if you want an attacker (Vaporeon) ir a substitute passer (Jolteon).
breed eevee with a ditto breed eevee with a ditto
Yes
Ditto.
To my knowledge (not there yet) I assume eevee is male and evee needs to female to mate with ditto (as all pokemon)