It's a common pattern for manga/LNs/VNs/games to be adapted to drama CD, and then to anime, and then to drama CD again but with the (often different) anime voice cast. Most series that are at least moderately popular seem to get at least one audio drama, so there's definitely a lot out there, too many to list.

One series whose audio dramas I've enjoyed is Aria. Aria has three drama CDs that were released prior to the Animation. The first two adapt selected chapters from the first few volumes of Aria, while the third goes back to adapt some from Aqua. They adapt the manga chapters more closely than the anime, close enough that you can almost read along while listening. Each CD also includes an original spin-off scenario. The cast and soundtrack differ from the anime, giving it a significantly different feel. It's an interesting taste of an alternative take on the series.
The rest of the CDs were released after the anime and use its voice cast and its superb soundtrack. Most, if not all, of them are composed of original episodes. Animation got 3 CDs, Natural 2 CDs, and Origination 3 CDs. Each TV season also got a Perfect Guide Book, with each book including its own bonus CD.
After Origination finished airing, the anime drama CDs (excluding the book bonuses) were collected into and re-released in drama CD box sets, one for each season, with each box also containing an original CD. Each anime DVD box set also came with an original CD. These audio dramas take place after Origination's ending and were released prior to Avvenire.
After Avvenire's release, Aria went on to get two crossover audio dramas with Amano's next work, Amanchu! (which also got some drama CDs of its own). The first crossover was spread across two drama CDs and the second one (>>/an/34678) across four drama CDs.
These are all the ones I know of, bringing the total to 20 CDs + 6 crossover CDs. The releases by Audio-4U (17 drama CDs) and NAOKI-Raws (for the 3 CDs newly included with the drama CD box sets) together cover these 20. If there are any I missed, I'd like to know.

To my knowledge, the few English-subtitled Aria releases are harder to obtain now due to dead links or a lack of seeders. These ones are still up:
https://www.mediafire.com/download.php?ktzmo39n2yl (MKV release of Natural Vol. 1, Navigation 4 by Sketchbook Picture Drama subs)
https://pastebin.com/raw/f2544aef4 (ASS subtitle file for Origination Vol. 1, Navigation 1 by Tortoise Fansubs; audio here: https://www.youtube.com/watch?v=2bi4TeHM4JA)
And here's a blog where most of the links are dead:
https://pokoteng-fansubs.blogspot.com/ (Note that the first post is mistaken about which one Tortoise Fansubs actually did.)

>>2704
By the way, from what I've gathered, the special edition of Vol. 1 of the Joshiraku manga came with rakugo by Kigu and Kukuru (the first link you posted, 二次限無 (officially read as にじゅげむ), based on 寿限無), and the special edition of Vol. 2 came with rakugo by Tetora, Gan, and Marii (your second link, 時かけそば, based on 時そば). The missing ones can be found here without subtitles (3D warning):
https://www.youtube.com/watch?v=PRm1IWgBTxQ 饅頭KY, based on まんじゅうこわい, performed by Kigu
https://www.youtube.com/watch?v=4bqMImF7780 刷毛もの使い, based on 化け物使い, performed by Tetora
https://www.youtube.com/watch?v=JbtGumocikw あたまヤマなしオチなしイミなし, based on 頭山, performed by Gan
The CDs also contain non-CDDA data, including, among other files, the script for each rakugo track.

In addition to these, the Joshiraku anime BDs were bundled with five more rakugo tracks, each track sharing its CD with a character song track. If you check the BD rip torrents or NND, you can see they've been ripped too. They are:
二次限無 Girl's Side, again based on 寿限無 but this time with a fujoshi twist, performed by Marii
元オタ, based on 元犬, performed by Tetora
二階メドキ, based on 二階ぞめき, performed by Kigu
ちくび指南, based on あくび指南, performed by Gan
尻神, based on 死神, performed by Kukuru

All 10 of these can be enjoyed without ever having read or watched the series, but, like with the series itself and Kumeta's other works, probably require a substantial familiarity with Japan and 2D otaku culture (and maybe also rakugo in this case) to fully appreciate. Admittedly, my power level wasn't high enough to catch everything, but my favorites were 時かけそば, 刷毛もの使い, and 二階メドキ.

>>2713
Since this post, the following have also been released:
- a drama CD for Aria the Crepuscolo (3 tracks, about 40 min. in total) starring Satou Rina as Athena in lieu of the late Kawakami Tomoko
- a mini voice drama (7 min. 15 sec.) about Akari, Alice, and Anya titled 『その　夜明け前のお散歩は…』 that was available for 12 months via streaming to customers who placed early pre-orders of the Crepuscolo BD
- a drama CD for Aria the Benedizione (3 tracks, about 50 min. in total)
Fortunately, they've all been ripped. See the releases by ReinForce or IrizaRaws.
This brings the total to 22 CDs + 6 crossover CDs + 1 streamed mini voice drama.

Something that may also interest Aria fans but deter 3D-haters is that the home video release of the movie version of Avvenire (as opposed to the 3-episode OVA version where one episode was included with each TV anime season BD box) includes a few recordings of 朗読劇 (plays that are performed by reading the script aloud; "recitation dramas"? "cold readings"?) performed by the seiyuu in front of a live audience. You probably could pretend that it's another audio drama and just listen to the audio and get by fine for the most part, but you might miss some things as the seiyuu do include some visual and fourth-wall-breaking components in their performances as well. The audio mixing isn't as good as the drama CDs either given that it's a recording of a live performance (although some seiyuu couldn't attend, so their lines were instead recorded in advance and played back live). See the releases by IrizaRaws or Moozzi2.