For Tin Ore

Alterac Ruins in Hilsbrad is the place to go!

For Greater Eternal Essence

Either runecloth headbands, enchant shield- greater stamina or grinding ST, BRD or BRS.

For Copper

I have found that Durotar is best for copper. There is a great deal just in the canyon around Razor Hill.

For Runecloth

Hellfire Ramparts is probably the best place to get this. Blood Furnace may be good, I haven't checked yet.