I enjoy Old-School gaming blogs for a couple of reasons. First is most of them like going over the roots of the hobby, talking about how things were not just out of the dreaded "N-Word" (Nostalgia) but more of an academic foray into games and the applications of those games. Sure the the is a bad signal to noise ratio at times with many blogs covering the exact same ground in the exact same way (and this blog is no exception to that) I am still entertained. Also the authors tend to be from the same gene-pool as me; metaphorically speaking. Not that I always want to listen to a bunch of middle aged white guys, but their interests are the same as mine; so if it veers "off-topic" into family, jobs, kids what have you, I don't mind. In fact most times I am nodding in agreement.
A couple of these Old-School+ blogs are the subject of todays The Best Blog You are Not Reading.
Billy Goes to Mordor
Billy Goes to Mordor has to win some sort of prize for the blog name that always makes me smile. Plus any blog that can put up a still from Ingmar Bergman's The Seventh Seal and not get all maudlin about it is doing something right. Around since 2011 and hitting half a dozen or so posts a month you can read through all his posts in a dedicated afternoon. There are thoughts on D&D, Horror and playing Pirates. Though I think his notes on Game Design are the most interesting. Insight on how another guy does his game.
A lot of thought goes into each post and really I think he is just a few dedicated followers (and regular commenters) away from really growing as a blog. Or maybe it is fine the way it is, but I bet some more followers would be appreciated all the same.
The Disoriented Ranger
Another Old-School blog around since 2011. This is a solidly OSR blog with links to free resources and notes on his RC based game. There are a lot of world building articles with his recent ones exploring "Karik Thel - The Island of the Floating Trees" which could easily be used anywhere so very much worth the read.
What got me into his blog was the day we both posted the same Racial Class within minutes of each other, Feline Humanoids vs. Cat Girls (I think it is easy to tell on name alone which is mine). In truth combining the two would make for a great class!
Like Billy, JD also posts more than just gaming material.
I would encourage you to check both blogs out.