No , wailmer evolve only by leveling it up it evolve at level 40 i think
you can find it on route 124 I've had a vulpix and to make it evolve i had find the red shard and i had to give it to hunter in mossdep city to get the fire stone
all you need is a blue shard and go to the shard maniac just of mossdeep and he will give you a water stone and a water stone can evolve starmie, and lotad :)
Near mossdeep ciry
I think he is near or in Mossdeep City.
Trade a green shard to the hunter to get a leaf stone.
its near the northwest corner of the route.
He is a little bit to the west of mosdeep
I found a red shard after using CUT on a few trees, it was lying around as an item. Was near Rustburo i think.
you can only get it by buying it at lilicove or change it for a blue shard
find a blue shard using Dive, and trade it to the guy by Mossdeep, or catch some clampearl, they hold blueshards too.
You Have To Use A Moon Shard And It Has To Have Max Hapiness
to get a red shard in emerald, you have to go to route 124. Hope this helped You have to dive underwater using hm dive and find them hidden in pale couloured stones, such as those you see in caves