I came here to get away from Reddit, but for Usenet deals, I don't know where else to track them. I haven't been on Usenet long enough to go through BF deals yet, but I plan on tracking https://www.reddit.com/r/usenet/wiki/providerdeals (for provider deals, obviously).
I've also seen provider reps post in the main sub (https://www.reddit.com/r/usenet/) with "terabyte Tuesday" & other similar type deals, but I can't recall if I've ever seen indexer reps post deals in there (pretty sure they don't, please anyone correct me if I'm wrong). My provider is Eweka, so I don't plan on getting any other provider deals, but I'll still take a look at what's available. Another good sub to track indexers might be: https://www.reddit.com/r/UsenetInvites/. Example: when Ninja (indexer) opened up registrations (temporarily no invite needed, about a month ago, supposedly very rare), it got posted in both of these subs.
Originally, my first provider wass a 2TB block from UsenetPrime (UsenetExpress backbone) and only completed 55% of the downloads I tried. I was extremely frustrated, and kept asking myself "this is what everyone else is saying is so great?" I did a lot of searching through various posts and then got the Eweka annual unlimited plan, and I haven't had any real problems since. I later picked up a 500GB data block from BlockNews (doesn't expire, & although they're under the same Omicron company name, they're on a different Highwinds backbone), just in case I ever ran into any future problems. Usenet.Farm ("Its Hosted" backbone) also had a deal that (if I recall correctly) you just signed up for an account and you get a 10GB block for free, and can get a 48% discount (code BDAY2023) when you're 10GB is gone and you're ready to sign up for a package (I'm assuming that code expires at some point though). With all these blocks I have, all of my DLs come solely from Eweka (according to SABnzbd stats). So I wouldn't buy any blocks (depending on who you're main provider is).
I've also seen a lot of people mention a combination deal of Frugal Usenet (Highwinds backbone, unlimited annual access, but limited retention), but it also has a 300GB or 750GB block with Usenet.Farm ("Its Hosted" backbone, supposedly longer retention period, more similar to Eweka) from Blocknews, for a little cheaper. So that may be another option for people to consider. Either way, I'd recommend not wasting money on UsenetPrime / UsenetExpress, or other data blocks unless you're having problems.
Just in case anyone is unaware of how backbones work, you should research it, and understand why you don't want to pay for accounts on overlapping backbones. Good tools for checking are: https://svgshare.com/i/iG8.svg -and- https://whatsmyuse.net/
My indexers are: DrunkenSlug (DS), NZBGeek (Geek), NZBFinder (Finder), NZBPlanet (Planet), NZB.Su (Su), and NinjaCentral (Ninja). So far, Planet and Ninja have been the most disappointing. Planet rarely comes up with something I'm searching for, probably well below 33% of the time. Ninja also rarely shows up with search results. However, the difference is, the rare times I've had a problem completing a file, I've then attempted to DL from the Ninja index link and I was then able to complete it, but that's been maybe 3 times? Planet just rarely shows up, to the point I forget I even have access to it. The other 4 indexers have all worked well. If there is another someone suggests, please let me know.
I guess I'll add, I got an invite to DOGnzb (indexer), but I soon realized you have to "buy" a shirt from them when paying for the account, and then if you want the shirt you just paid for, you have to actually pay for it again. Maybe it's a decent indexer, but it's extremely expensive, and I haven't had a problem with my other indexers, so I deleted the DOG account & never tried it.