Seeing as it's Friday and I'm bored at work. Thought I would work out a rough price for levelling each crafting profession, as it's been mentioned a few times and I had a feeling that what I thought was the most expensive might actually be the case.
So I decided to work it out and here are the results.

These are the average costs of the raw materials required to level each crafting profession. This includes vendor bought items such as vials and thread. The only cost I haven't included is the training costs. But on average you can expect to pay about 30g for training costs for 1 to 300 and about 100g for 300 to 375.

Alchemy

1 to 300 = 125g

300 to 375 = 240g

Total Cost = 365g


Blacksmithing

1 to 300 = 883g

300 to 375 = 3324g

Total Cost = 4207g

Enchanting

1 to 300 = 726g

300 to 375 = 4116g

Total Cost = 4842g

Engineering

1 to 300 = 231g

300 to 375 = 2516g

Total Cost = 2747g

Jewelcrafting

1 to 300 = 231g

300 to 375 = No Price Yet (really can't bothered to work it out at the moment)

Total Cost = 756g

Leatherworking

1 to 300 = 171g

300 to 375 = 1773g

Total Cost = 1944g

Tailoring

1 to 300 = 240g

300 to 375 = 1141g

Total Cost = 1381g



So Alchemy is the cheapest to level all the way from 1 to 375, by a long way. I expected that, so no surprise there.
Enchanting is the most expensive, followed by Blacksmithing. I'm not really surprised, seeing as this would be the cost if bought every single mat off of the AH.
But realistically you're not going to do that. An enchanter will DE a lot of those mats and a Blacksmither will mine a lot. In fact about 75% of the cost for levelling Blacksmithing is the primals required to get from 360 to 375. 75% of the cost for 15 points!! But if you got the felsteel plans, you could knock off over 3,000g off of the cost of levelling BS.

I didn't do JC 300 to 375 as it varies way too much. You could spend as little as 100g or as much as 5,000g.

So to my mind, Engineering is the most expensive to level as there are not a lot of options for cutting costs, except for mining endlessly to gather the mats needed.

Price data is taken from http://www.wowecon.com

---

Q u o t e:
Interesting post. Quick point: You've got enchanting 300-375 costing 41160g ;)

---

Lol, better change that :)

---

Q u o t e:
For the JC to 375 going by picking the stuff up from the AH I'd say between 1600 and 2000g.

Buying the ore and prospecting it would lower the price a bit (at least on Arathor with adamantite @ 20g ).

---

But with the "drop rate" of blue gems from prospecting being fairly low, it's extremely hard to put a monetary figure on it, because one person's luck can vary so wildly from another person's.

Though my gut feeling says, your probably about right with that figure.

---

Q u o t e:


*You're :p

---

Thank you. I have a real blind spot for that.

My excuse is that I was too hung over to wake up in time for my English exam.
Getting served in Pubs at 15 FTL :(

Erm....no. I'm not 15. I was 15, 21 years ago.

I iz an old gitz :)

Thank you for the post though :)

Material	Quantity	Cost in G per item	Total Cost

160 x Linen Cloth	160	1	1.60

200 x Wool Cloth	200	6.66	13.32

760 x Silk Cloth	760	3.75	28.50

520 x Mageweave Cloth	520	9.4	48.88

900 x Runecloth	900	10	90.00

120 x Rugged Leather	120	17.5	21.00

75 x Coarse Thread	75	0.1	0.08

135 x Fine Thread	135	1	1.35

5 x Gray Dye	5	3.5	0.18

30 x Blue Dye	30	0.5	0.15

10 x Bleach	10	0.25	0.03

60 x Red Dye	60	0.5	0.30

45 x Silken Thread	45	5	2.25

60 x Heavy Silken Thread	60	20	12.00

40 x Rune Thread	40	50	20.00

				239.63

2460 x Netherweave Cloth	2460	22.5	553.50	

180 x Arcane Dust	180	200	360.00	

35 x Netherweb Spider silk	35	571.42	200.00	

35 x Rune Thread	35	50	17.50	

20 x Knothide Leather	20	50	10.00	

			1380.62	1141.00

Cant be bothered to format it. Sorry.

The prices are the average price as seen by WoWEcon.com. This is the average price across factions and across all servers.