You can either canoe or hike in. To hike go to Google Earth and find the locomotives. Then look to the northwest for a road. Then follow the road back to Baxter State Park. It takes about 2 hours to drive to the trailhead. About 1/2 way there's a guard shack you need to stop at and pay $5 to enter the forest lands. The person at the guard shack can usually help you find the locomotives. The hike is about 1.5 miles in through slightly swampy forest (nothing serious, but be on the lookout for moose!). I lucked out and saw only moose tracks and a few mosquitoes. Someone has put plastic flagging on the trail anytime it gets faint. Be sure to hike over the the other lake to the south to see the terminus of the log chain tramway.
Here's some more photos: