[denydenydeny]

Go to Google and click on "google groups" and there you are.

[lelio]

The easiest way is to go to Groups.Google.Com and read & post from there.
You could see if your ISP has a news server, it is probably "news.myispname.com" and you should put that into your News Server settings in your newsreader.
If you do the above you should also be able to broswe the list of available newsgroups.
I would start with Google first though, very easy. Extremely useful especially if you're doing computer work and need an answer

[Keith in Iowa]

First, check with your ISP - many have a server you can access that they maintain, or they get service for their customers from an outside provider. If your ISP does not provide the service, there are a number of commercial services you can get newsgroups throug - search Google or Yahoo for "usenet news providers" - one I am familiar with is called AirNews...

[Benrand]

DL Forte Free Agent from Tucows or the Agent website. Find out your newserver at your ISP, it'll be something like news.xxx.xxx and go into the program, enter the host under preferences and you should be set. It's pretty easy. In fact, Google has newsgroups. You can access them through Google's main page.

You have to register.

[dennisw]

FREE: Good free new server you can post also. Must register with them. I had to wait a few weeks to be accepted but maybe they are better now 
http://news.fu-berlin.de/

FREE: These guys are good..... many good newsgroups and it moves fast. Read only no posting. You can read here and post via google if you like:
dp-news.maxwell.syr.edu

[Texaggie79]

BTW, if you are serious about newsgroups and are willing to pay for them. There is nothing better than Usenet.com

[Sawdring]

This is a good one:

alt.war.nuclear

[xmarksthespot]

Read other posts and study the responses to those posts

[babyfreep]

When you finally do get a good list of ng's (there are thousands), for an introduction to Usenet and info about "netiquette", check out news.announce.newusers. It is a "read-only" group.
You can post your questions to news.newusers.questions
There are newsgroups for every subject under the sun, and then some. (There are a few kooks out there who create groups with some really nonsense names just to be "kooky", especially under the "alt." hierarchy and a good percentage of those are left empty.)I like the alt.politics.*** groups.