For what it's worth, if you aren't powerskilling enchanting to 300 it isn't bad cost wise. Miriallia was skinning/herb originally, but i switched from skinning to enchanting around lvl 50. I powerskilled up to around 150ish skill (just reenchanting one of my bracers over and over, etc), that probably cost me 30-40g. After that though, I just took it slow, advertising popular enchants that would provide skill up (+dmg, stam, etc) and selling them at cost of materials or a small loss. You can check the list of materials for each recipe on alla or thottbot and then use the AH to figure out what the cheapest enchant is to powerskill on.
Because enchants are a bit more "on-demand", I think it's easier to not get in a financial hole like some of the other production skills that might have you making lots of inventory that doesn't sell.
Not counting buying some of the more expensive recipes, I actually made a decent amount of money by the time I hit 300. Remember to disenchant any greens you get, and to still charge AH cost of mats for the mats you provide - that helps to absorb some of the cost too.