Venture Co. Mines is where to go for Engineer Trainer in Mulgore, as someone already mentioned. Here's some slightly more detailed directions:
Go to the Venture Co. Mines. They are located in E/NE Mulgore, directly east of the Burning Caravan. There are a lot of level 6-9 humanoids in here, but you can typically pull them one at a time if you are careful.
Once you enter the mines, look at the minimap. You want the western exit from the mines. The exit is east to see on the map because it is one of the longest tunnels that appears to dead-end. Go through this exit and you will find yourself out on the cliff overlooking Mulgore.
Turn right (~North) as you come out of the mines. You will have to walk along the ledge for a short distance, and then will come across a gnome next to a tent by himself. The gnome is the engineering trainer.
Edited, Thu Jan 27 09:27:24 2005 by garfunkel