Travel to Dragon Stone and talk to Galanoth. He has a shop that sells dragon slayer armor.
A forest & desert dragon should make an armor dragon.
Forest & Desert dragon should make an Armor dragon in Little Dragons.
dragon scale armor is a new type of bullet resistant vest
You have to buy Dragon Armor.
There is no Dragon Priest Armor, only their masks.
There is no vampire armor.
Go to galanoth in Dragesvard and the click the button that says become a dragonslayer. (Note: you have to have a dragonslayer armor by having an ice dragon scale in Galanoth's random quests.) Click the button that says train. Do the quest and roll the red button in the end. If you have 70 and up you get one enchanting stone. If you get 70 and below, you don't get an enchanting stone. Galanoth will teach you a skill if you give him an enchnting stone. (Note: you don't need a dragon amulet to have a dragonslayer armor) I've completed one of Galanoth's random quest and I got an Ice Dragon Scale. Galanoth gave me a Dragonslayer armor when I gave him an Ice Dragon Scale.
There is no such thing as dragonwarrior armor on runescape. If you mean dragon plate armor, you need to have level 60 defense to be able to wear it. Dragon plate armor has good defense bonuses, but it is a little expensive. To get dragon plate armor you can but it at the grand exchange or buy ir from players. Some monsters on runescape drop dragon armor but it is usually a rare drop.
you can't but there is iron armor which looks like stone
The Great Dragon will always be a Great Dragon, but it is relatively useless until you fully armor it. You can find armor at Lv 5+ Anthropus Camps, the higher the level higher the odds of armor getting dropped.
Buy better armor.