USENET - how to join "other" newsgroups ?

[#1]

I understand how to access the various Plusnet newsgroups using the web based news reader on this site and how I can configure OE to do something similar.
What I'm unclear abou is how I can join other newsgroups
e.g. alt.binaries.sounds.radio.bbc
Who do I apply to and how do I apply.
I'd also like to know how I can use an NZB file to retrieve specific content - what tools does to work with ?
Brgds
Chris - London

[#2]

You need to sign up with a news provider, like news.astraweb.com or usenetnews.com who provide the binary newsgroups. (not free BTW)
To use a .nzb you need a reader (I prefer sabnzbd or newsbin) that will take the nzb file and download the content for you. (Sabnzbd is great if you just want to download files where as newsbin will display the items for you to read and download them as well)

[#3]

Thanks Hairy Biker !
So will that give me access to all news groups ?
What does the plus.net one offer me ?

[#4]

Using a text newsreader (e.g. Thunderbird) you can access over 100,000 different text only newgroups on the Plusnet server for free.

[#5]

Yes using either of the providers I mentioned (or many others) will give you access to ALL the newsgroups. The PN one gives you access to the TEXT only (i.e. chat) ones ONLY.
So no access to a.b.sounds.radio.bbc or a.b.old-time-radio for instance from the free one.
If your usage is likely to be small then <a href="http://www.astraweb.com/">astraweb</a> offer PAYD where you can buy a (non expiring) block of d/l bytes. Or if you can see yourself downloading more then they offer unlimited packages from $10/month.
E.g. a block of 25Gb is $10 or 180Gb for $25 that's quite a serious amount of data!