look at your download in emule for a minute, make sure you read all the information.
There are columns called "Last Seen Complete", etc. which obviously tells you when you last saw a full source. If you double click on the download it will expand into individual sources. If you see someone who has the bit you need, right click and send them a message asking to up the priority of the download.
As for reshares, there's a section at the bottom of these forums for a reshare.
I wouldn't recommend jumping the gun on a download, just wait for it to complete