You have posted in the wrong place. This is for Phex New users, not Limewire.
The files you download are just files ... mp3 or what ever. If you can upload them or a link to them to a yahoo blog I don't know. You will need to read the instructions, carefully for the blog. It may be you need to upload the file to the file hosting service, who will give you a URL for it. This is how many Picture uploads are done.. music I don't know about. and you will need to get the file from it's destination folder on your computer rather than the Limewire Library.
I hope this helps a bit.