It's been hard to find in-depth information on the old days of Kitakou and Barjona, but sometimes I'm able to get lucky and find Web Archived versions of Himaruya's other sites that contained information and images on the m.
The main Kitayume site (Geocities.jp/himaruya) is robots.txt'd and blocked from the Web Archive, but you can find old versions of some pages on the Japanese "Megalodon" archive (but only from 2007, with about two pages from 2006).
There are also two sites still in existence that have some KitaPure and Barjona game info saved over too: "Himaruya2" (which is also robots.txt'd, so you can't find any earlier versions on the Web Archive) and "Barjonajp". It's interesting to see just how many sites he has/had. He also had a Livedoor blog back in '04 or so for Kitakou, to add to this listing. Himaruya's other hosts like Wotaemon and Side-B have turned up some results in the Web Archive too.
As a further note, Himaruya himself writes Kitakou's title in English as 「Progress! North Industry Broadcast Department」
I'll make a post later on what you can find hidden on Kitayume nowadays, maybe.
Stuff from Side-B and Barjonajp
- icons! If you click on the "kabe" link you can see wallpapers, but sadly their bigger versions were not archived with the thumbnails. Twin-tailed Noto is too cute.
- A later version of "Omiyage" Different set of icons! Interesting how Imari's hair was red in the earlier set, but pink here. The Engrish is amusing.
- Kitakou Pure game page Well, one version of it. You can find info on the voice cast and details about the game, but I'm not too good at translating huge chunks of Japanese |D.
- Kitakou Pure characters Pictures are mostly broken, but if you click on the Iwase and Seiryou sections you can find images for their character lineups.
- Oh, St.MODERN Cute pic of Rinko on this page. There used to be pages specifically for the seifuku, but as the images didn't get saved, they're not worth looking at archived.
- In-progess pic of some familiar students
- Barjona icons Self-explanatory, but they're Christmas-themed.
- The first version of the Barjona page, July 2004
- August 2004 Profiles were added, though Nacchan's was not saved. Kalom's is adorable.
- Barjona character blurbs
- Nacchan with pigtails and Italy curl? Idk
- First appearance of Yamato, October 2004 screenshot of a Barjona game
- Barjona game that introduces Yamato? It's the title screen
- A Barjona game page?
- Barjona preview? Includes an OLD e-mail address of Himaruya's, doubt it works anymore (don't bother trying anyway, fff). I've seen other two old e-mail addies of his pop up on archived pages too.
- The early Barjona cast, so cute
- Azumi uniformsPics are broken, but info is still there.
- This frightens me What is it?
- Pages 2-6 are missing Seems like it's a roughly-drawn Kitakou comic.
- 8 There were 17 pages, all but 1, 7, and 8 seem to be lost.
Chapter 15 of Kitakou was published in December 2003, if the archives are right. Chapter 16 was January/February 2004. 17 itself was January. There was also an original chapter 18, but I have no clue what it contained as it doesn't seem to be archived.
- Screencap from a game
- Interview with Noto and Hinaji?
- Noto and Toyama comic, page 1
- Page 2
- St.Azumi logo
- Barjona game cast
- Samples of the Barjona game! The pictures still work, too
- This looks like Toyama with a guitar, but idk
- Something about Hatoba
- Some page about Hinaji or something
- That fantasy Kitakou comic, but what happened to pages 1, 3, and 4?
- An Xmas comic with Noto, the pages work. Well, the first four. Seems it totaled 18 pages.
- A story of how Noto and Toyama met as kids. The first six pages work.
- Another Kitakou game page
- Scrapped/incomplete Kitakou and Barjona works
- A Pure-era comic
- A picture of Hatoba with a lion
- Hinaji and cat
- Promo pic for Pure, note the pink-haired Imari
- Miyako sketches
- Page 6 of some comic with a creepy style
- Profiles on St.Modern and Azumi?
- St. Modern North Industrial High School is how Himaruya translates Kitakou High completely
- Rinko wallpaper
- Sunki wallpaper
- Megane Noto comic?
- What is going on here
- Strange. And it seems there are three pages missing after this.
- Page 4 of some comic, first three pages missing
Comic, first page missing:
The Barjona game page does not seem to have been archived from Side-B, unfortunately. But this site has a character page and other things:
- A bonus page on Seiryou
- Natu? Oh, it's Nacchan without the heartcurl
- Aww, "Tama"
-  Old page for Nishiko, so cute
- Tira? Tyla?
Pages from Himaruya2
- Old page with Seiryou graphic and defunct Barjona download
- A graphic of Black Noto from the game can be seen here
- Spain from Noto-sama 5
- June 2004's diary/update log A chibi of Hinaji in his red school uniform is on this page.
-  Sketches of Kalom from a link within that log.
- Diary/update log from July 2004 The "gisogamaso" link within has some interesting doodles, but I don't know what of. This page also has cute Kalom doodles.
- Diary/update log from August 2004
- September '04 It seems September 2004 was when the "Black Noto tortures Himaruya" and "Black Noto goes after the Barjona cast" comics were posted. So Black Noto did debut in '04!
- October '04 It seems his Side-B site expired in late 2004 or sometime in 2005, so Side-B links in these generally don't work unless the Web Archive has earlier versions saved. Himaruya really likes donuts, it seems (Mr.Donut!). This page also has the lyrics to what seems to be the Kitakou Pure ending theme.
- November '04 It seems he was still working on the "Black Noto terrorizes Barjona cast" comic at this time, among other things. It also seems "LiveALive" was a '04 comic.
- Tengoku? Interesting doodles on this page
- December '04 log...I spy a link to a Yaranaika, pfff.
- Yaranaika? again
- Oh man, so cute Barjona character designs of Kalom, Tsuko, and Sunki.
- Looks like a caricature of Himaruya and someone else, not sure
- A screenshot from KitaPure with Imari
- Some Kitakou game page
- Uradesuyo! Cute pic of Noto.
- Kitakou cast in swimsuitsI think it's fanart or he did a total style shift.
- Noto and Toyama!
- January updates for 2004 It seems like chapters 16-17.5 were done in January '04, which means there is quite the giant gap between those chapters and chapters 18 and 19 on the current Kitakou page (not to mention all the deletions of material). On this Livedoor page, there is a link to that fantasy-themed Kitakou comic on Side-B that only one page was saved in the Web Archive. It's a shame! You can see pictures referencing the comic though, like Noto with the Chako(?) fairy and Rinko as a witch.
- Updates for May
- Chibis scattered about
The sakura.ne.jp site seems to have been down for quite a while, and even Megalodon's archives seem to be failing now. But there is always the Web Archive:
- Notosama 4? Looks like it! Seems that it came out in early '07, and Notosama 5 was in mid-later '07.
- Page for a Barjona game opening, seems to be in the series that became Notosama
- Notosama 3? This one's from 2006.
- Not quite Kitakou, but Notosama 5-related Hungary!
- Some Barjona game
A comic about Imari:
Extra: Barjona voice cast
Been trying to translate/figure out both this and the Kitakou/KitaPure voice cast. But here it is: