This Web site should contain all of the information you need:
http://bulbapedia.bulbagarden.net/wiki/Starmie_(Pok%C3%A9mon)/Generation_III_learnset
trade from leaf green or fire red
No, you cannot. You have to trade Starmie over to your FireRed from either Ruby, Sapphire, Emerald, LeafGreen, or Pokémon XD: Gale of Darkness.
The Pokémon in Sapphire who have the Illuminate ability are Volbeat, Staryu/Starmie and Chinchou/Lanturn.
magickarp horsea tetecool starmie shelder the rest i forgot :P
Starmie learns the following: When you get it: Water Gun, Rapid Spin, Recover and Swift, then at level 28 it learns Confuse Ray.
It doesn't learn Ice Beam by level. It is, however, able to learn it through the use of the Ice Beam TM.
Yes, Marill can learn Surf.
No, Sceptile cannot learn Blizzard.
The following Pokemon that you can easily get to learn Flash in Sapphire: Beautifly or Dustox Lotad or Lombre Oddish Gloom
No, Heat Wave is a Generation IV move. Sapphire is a Generation III game. CHARIZARD can't learn it with Sapphire, but Diamond, Platinum, HeartGold... they'll all work!
No, Starmie don't evolve further.
Linoone and Slaking.