This guide will provide you with the fastest and least expensive way to level your Engineering skill up from 1 to 600. The guide is up to date for WoW patch 5.0.5
Engineering is the best combined with Mining. This way you can collect all the necessary items yourself and save yourself a lot of gold, otherwise you will need either a guide (or friends who are happy to help) or plenty of gold!
• 60 x Rough Stone
• 36 x Copper Bar
• 20 x Coarse Stone
• 20 x Linen Cloth
• 95 x Bronze Bar - 48 Copper Bar + 48 Tin Bar
• 4 x Moss Agate
• 30 x Heavy Stone
• 60 x Wool Cloth
• 15 x Medium Leather
• 4 x Steel Bar
• 120 x Solid Stone
• 161 x Mithril Bar
• 20 x Mageweave Cloth
• 40 x Dense Stone
• 189 x Thorium Bar
• 21 x Runecloth
Burning Crusade
• 95 x Fel Iron Bar
• 20 x Mote of Earth
• 10 x Mote of Fire
• 40 x Adamantite Bar
• 30 x Netherweave Cloth
Wrath of the Lich King
• 210 x Cobalt Bar
• 8 x Frostweave Cloth
• 20 x Crystallized Water
• 10 x Crystallized Earth
• 35 x Tinker's Kit
Cataclysm
• 85 x Obsidium Bar
• 4 x Alicite
• 52 x Volatile Earth
• 30 x Volatile Air
• 76 x Elementium Bar
• 20 x Embersilk Cloth
Pandaria
• 85 x Windwool Cloth
• 90 x Ghost Iron Bar
• 1 x Spirit of Harmony
• You will also need about 4 more [Spirit of Harmony] or 300 [Ghost Iron Bar] depending on which items you make.