There are many Usenet providers out there, and the price range and services are typically the same. All I suggest is just trying a few on a trial period if they offer one, and if you don't see any mention of this, then contact them, as most are willing to offer a trial period.

Usenet providers:

Airnews.net

AlltheNewsgroups.com

Altopia

astraweb

Binaries.net

Easynews

Giganews

newsfeeds.com

Newsdome

newsgroup-binaries.com

newsgroups.com

NewsHosting.com (Personal Favorite) :icon_thum

newsreader.com

Newscene.com

news-service.com

NewsWorld

Newsville

NuthinButNews.com

Power Usenet

Slurp News

Supernews

Tera News

usenet-access.com

usenet.com

UseNetServer.com

Usenetworld

1usenet.com