I personally use Teranews. They give good value for the money, carry all the newsgroups and have decent retention. They have a "free" account where you pay $3.95 once and get 50MB per day forever. You can use it to try it out. If you like, you can upgrade later. You can also sign up monthly but it is cheaper if you go for the 6 month plan.
I'll get credit of you use my referral link:
Here are a few others:
I use Teranews because if you get one of their by-day plans you really get more downloads and I personally prefer by-day download limits. For instance, say you get the Teranews 250MB per day plan for $8/month... That is really 7.5GB/month for $8/month when you come to think of it. If you get their 750MB/day, you are getting 22.5GB/month for $12/month. Whereas Giganews, for instance, only gives you 10GB/month for $12/month. Easynews provides excellent service (I've used it before) and has a good deal at 20GB/month for $10/month. But if you get a 6month plan Teranews gives you 22.5GB/month for $10/month ($60/6 months). A couple of years back Easynews was not quite providing access to all groups but they gave access to most. Their retention was a little bit better than Teranews' back then.
So Astraweb is really giving unlimited downloads for $10/month? That seems too good to be true. There must be a catch. Do they have crappy retention or a poor newsgroup selection?