Rotom cannot be evolved
no, Rotom never evolves. Rotom has different forms which are not in diamond pearl.
No but you can change its form in Platium.
you can't rotom has five different forms, which are only in platinum, with an event.
Rotom doesn't evolve.
Tynamo will evolve into Elektrik will evolve into Elektross with a thunderstone in Pokemon White.
Emolga does not evolve. I played Pokemon White also and it does not evolve. Some Pokemon do but this one does not evolve.
trade for a ditto at route 14.
Rotom can't evolve, but it can change forms. Is this what you mean?
you mean STUNFISK in Pokemon black and white, and no he does NOT evolve at all
Audino doesnt evolve in Pokemon black and white
Throh don't evolve in Pokemon Black and White.
On Route 15, there is a little trailer right before you leave and in there, a lady will trade you a rotom for a ditto.