WoW's economy is insane, broken.
4 pieces of Medium Leather cost 39G on EU-Twisting Nether (Horde, don't know 'bout how things are on Alliance side).
Noobs cannot afford that, experienced players don't need it (or if they do, very little). Since there is no need, the price should be low. But no, WoW's insane system means inflation is insane.
So. Where the hell am i going to get 4 pieces of Medium Leather? Guild has a lot of people but they don't talk nor do they listen (a random guild that invited me, accepted for the perks).
I'm not very keen on the idea of waiting in Orgrimmar trying to WTB them from trade chat. Going to take a long while.
EDIT oh, there's a NPC that sells it. Hmm. Let's try that then.
That's how a player controlled economy works. The point is, it works the other way too.
Pick up some professions and start putting stuff on AH, you'll also make a lot more money to buy this stuff. Ores, leather, plants basically anything profession related will net you gold quickly.
If you're a first time player I'd say a gathering profession is a must if you haven't picked one.