Usenet newsgroup selection depends on the news servers and what they subscribe to. Torrents are pretty easy. You usually have a folder of the contents that you want to torrent. Use a program such as MakeTorrent to generate the *.torrent hash for the files, and then you upload the generated file to a tracker. Whoever on the tracker download the parts of the files and then it finishes after a while.

What is usually slow is that the seeder tends to upload to a particular user that's close to him in the p2p network, but the user doesn't necessarily reciprocate the same download speed for their upload speed. This can be solved by going into the super seeder mode, where the seeder forces the recipients to upload as much as possible, thus spreading the uploading task from one user to many.