As far as I am aware, Usenet is a subscription service -- Atleast most of the more popular communities.
You can get cheap subscriptions from various online providers which will give you access to the content on the newsgroups.
I might also be interested in posts from alt.binaries.*
From this, I undestand that you'd be interested in mirroring the content. I really don't recommend this due to the insane amount of information that is posted on the more active groups daily. You'd need a VERY fast internet connection and industrial-level storage.
Now, if all you want is to access some of the posted content, simply get a subscription from one of the many providers, download SABNZbd+ and use online usenet search engines to find content.