'Heithur Ironfist was telling me about the missing dwarves while you were away, (player name). Glóin of the Lonely Mountain requested the delivery of some stones of historical value from Thorin's Hall as a sign of good faith for the Elves of Rivendell -- he is visiting Imladris on a mission of some importance -- and Heithur is worried that Glóin will be made a laughing-stock without such gifts.
'He is mistaken, of course. Master Elrond treats all with respect and honour and has no need for such baubles. I have told Heithur he need not worry on that account, but he does not listen.
'Perhaps the dwarves were surprised before they had come very far into the Trollshaws, (player name)? Speak with Alphlanc at the Last Bridge...perhaps she has seen some sign of their passing.'
Heithur Ironfist is concerned about his missing dwarves, but he is especially worried about their cargo of historically-significant stones from Thorin's Hall bound for Glóin, and he wants them recovered.
Speak with Alphlanc and search the area around the Last Bridge for signs of the dwarves disapearance.
Speak with Alphlanc
Alphlanc is at the Last Bridge on the western edge of the Trollshaws, where the road passes into the Lone-lands.
Barachen has asked you to speak with Alphlanc at the Last Bridge to see if she has seen sign of the missing dwarves.
Search the area around the Last Bridge
The Last Bridge supports the road as it winds west out of the Trollshaws and passes into the Lone-lands.
Alphlanc has asked you to search the area immediately around the Last Bridge closely for some sign of the missing dwarves.
Search the smashed crate
A smashed crate lies at the foot of the Last Bridge, on the water's edge.
You have located a smashed crate by the Last Bridge that appears to be of dwarf-make. You should investigate further.
Return to Heifer Ironfist and inform him of your find.
Heithur Ironfist is at Barachen's camp, east of the Last Bridge, on a sloping hill in the shadow of the southern cliffs. The Elf Rochwen stands on the road north of the camp, ready to aid travellers.
Heithur will want to hear about your discovery of a shattered dwarf-crate at the base of the Last Bridge, emptied of its contents.
The "evidence" you're looking for is a smashed crate near Alphlanc. 5-10 seconds away, near the water.