Newzbin:Limitations
From Newzbin Documentation
Newzbin indexes Usenet, the public distribution network. Any newsgroup which is designated as a 'binaries' newsgroup and contains multipart binaries, is scanned every hour or so, and information about new postings is stored in our database.
Note that we only store metadata about the posts, we do not store the actual binaries themselves. Therefore, you cannot get these binaries from Newzbin. You can only get information about them. Hence, Newzbin's strengths lie in indexing these newsgroups and letting you search them, seeing what's on Usenet at a glance.
Any multipart binary, by and large, is indexed.
Most single-part binaries are discarded. For example, images/pictures.
There are some exceptions to this rule, ie, 'nfo' and 'sfv' files. These are related to multipart binary posts and are thus relevant to our index.