With so many great professions to level in World of Warcraft, there’s no good reason to not try them all. You may have alts (character other than your highest leveled character) to develop new professions. You can also switch professions on your main (you probably have this figured out; main is the character you play the most) to try out a new profession. You may simply decide that another profession will work out better for Arena or PVP play. You may even decide to drop a gathering profession in favor of a crafting profession.
This section of the guide will help you level a new profession in a rush. To do the rush-leveling, we’re assuming that you’re doing it on a high-level character (most crafting professions have quests that must be accomplished or instances to be run). You’re also going to need lots of gold for this. Some of the mats (materials) you’ll be using can be purchased in the Auction House. Some mats you’ll have to acquire yourself.
Skill-Up Helps
http://wow.crafterstome.com/recipes.html
The above link goes to a web site that lists recipes (and ingredients) for all the professions.
Www.thottbot.com offers a similar page for each profession.
Training Locations
From the official patch notes:
All primary profession trainers outside of capitals (Alchemy, Blacksmithing, Enchanting, Engineering, Leatherworking, Tailoring) have been changed to train up to Artisan level (skill level 300) in their respective professions.

The capital cities now possess Artisan level trainers for the primary professions they support, and are surrounded by their newly-dubbed Apprentices where applicable.