Newshosting, one of the better Usenet providers within this industry has undergone a much needed makeover with a newly designed website, better information on their different payment plans and a much more informative support section including video screencasts about usenet. They cover configuring 4 seperate clients and then searching, downloading and posting in those clients.
Out of the 4 clients they provide videos for, Newsbin Pro and Unison would be our choice for dealing with binaries (files) depending on whether you're on Window or Mac respectively; Thunderbird would get our choice for reading text newsgroups; and Outlook Express would end up in the recycle bin - we don't recommend the use of that (old and non updated) program for Usenet access although I shall not deny my first venture on to Usenet all those years ago was via Outlook Express!
If you're interested, Newshosting offers a 14 day free trial and give free SSL connections with all packages, something we wish other providers would offer. They are also definitely up there in terms of retention, 422-430 days at time of publishing, giving direct competition to Giganews' 451 days.