You can get them many ways, such as mining, or simply running around sinnoh and finding them.
You can get one in sunyshore or u can dig for one underground
The Underground or Sunyshore City
I'm not exactly sure ,but i think you have to go underground and dug it up.
You can't find it; it's not like that. If you got the Eevee from Bebe, use a Thunderstone on it and it evolves.
You can get one in sunnyshore city or underGround
Pokemon 135 is a Jolteon you must get and evee and put a thunderstone on it!
pikachu evolves into raichu if you use a thunderstone on him other Pokemon evolves to if you use it but i don't now them DIAMOND AND PEARL ONLY
A Thunderstone can evovle Pickachu.
one place is in the underground
In sunnyshore city in front of the lighthouse there is one on the ground
no, you can only get them from using the explorer kit or sunnyshore
You use a thunderstone. I did Riachu is amazing!