You may get Blue Gummies in rescue missions and or Outlaw Rewards or otherwise the mystery dungeons
you can find blue gummies easily in craggy coast if your getting it for phanpy or w/e its called you will need 2
go to upcpokemon center to make your own wonder mail(wifi needed)
Actually manaphy (when you get to that part) says craggy coast is a OK place for blue gummies (gummys to manaphy)
Source
Own Experience
You can either go to craggy coast and try to find 1 (2 if its for manaphy as he will want one the next day) or you can try to buy one from the kecleon market or dungeon shops or you can try to get one off the bulletin board or you can go to this site:http://www.upokecenter.com/games/dungeon2/guides/wondermail.php and create your own wonder mail for the reward a blue goomi (lol) and for you to just rescue some1 on the 1st floors of beach cave enjoy ;) (also if you're going to craggy coast it may take a bit of time because i got 2 on the 2nd try)
Source of this information:
Own Experience and ideas (kecleon market was an idea)
Yellow gummies.
You can usually find them at Craggy Coast. If not there try Marine Resort, if unlocked.
No, you can not get Lucario in Mystery Dungeon Blue.
with gummies. Try to give Pokemon it's favorite gummie by looking at gummie's descriptin
At http://www.upokecenter.com/games/dungeon2/guides/wondermail.php you can use a wonder mail generator. :)
you can't trade on Pokemon mystery dungeon OK
Yes there is a unknown dungeon in Pokemon blue mystery dungeon! You'll have to connect with your friends if you want to go there
buy it.
nope
You can find blue gummi's EVERYWHERE. Most people say that the Marine resort has a load of gummi's
No, only joy seeds are available in Mystery dungeon Blue and Red
yes all Pokemon evolve in Pokemon mystery dungeon blue rescue team after you beat Rayquaza and legendary Pokemon don't evolve.