Since Aeth is now an enchanter, I dropped that profession on Laenshield and picked up alchemy. The total time to level was about the same - a couple of hours a day over 2-3 days for collecting mats, picking up recipes, etc. - but the overall cost was vastly different. It cost Laenshield less than 3k, total, to level alchemy, and even that's probably on the high side, since I'm still making money off of selling the potions, elixirs, and other items he produced while leveling.
Granted, I spent a couple of hours on Aretae gathering herbs for Laenshield before I started leveling alchemy. That wasn't really to avoid spending gold on the AH, though. Truth be told, there were almost no low-level (pre-BC) herbs on the AH at all. Given that, farming up what I needed was the only real option I had.