I think its sh*t when this sort of thing happens,you should'nt just have to deal with it,after all its your hard earned,its all well and good saying collect the item to be safe but sometimes its not that easy or convienient and if the seller of said item offers postage as a service then should have the decency to protect the item with sufficient packaging
I suggest putting up a post on the forum where this person is a member,you dont even have to give full details of whats gone on(well not at first depending on if he answers)generally it seems people that dodge emails or pm's to try and wriggle out of a potentially tricky situation will often reply to a post on the public forum as if they dont it wiil soon become clear to all whats gone on,thats my opinon anyway mate,i hope you get it sorted