Pundit's main interest seems to be creating and refining settings, but I see he publishes adventures in his 'zine, as well.

https://www.drivethrurpg.com/m/browser/publisher/Spectre-Press/451

Is there a list of just his adventures, as well as a ranking of them?

The first that catches my eye is "The Elven Tomb"; is it appropriate for beginning levels?

I'm not aware of any master list of the Pundit's adventures, but I do own the Old School Companion 2, which includes the Elven Tomb Adventure.

I've considered doing a review of the book, but never gotten around to it. The big points to know going in are that the adventures are around 10-15 pages long on average, with no maps, they're stat-ed for his Lion & Dragon game, and mostly presume playing in the Dark Albion setting. So expect to be doing a fair bit of additional work on top of what's presented in the module, especially if you aren't playing Lion & Dragon.

I ran a heavily converted  and altered version of The Elven Tomb for Dragon Warriors, so I can't exactly speak for how it runs in L&D. The adventure includes the following quote:

"This is a fairly dangerous adventure, so it would probably be best for mid-level characters. Very low-level adventurers might find it overwhelming, although that could also be fun."

I would personally not run it for low level characters in a general OSR game. Trying to limit spoilers, but the adventure puts the PCs up against a large group of bandits, with several mid-level characters among them. The tomb itself is light on encounters, but includes a couple of save-or-die traps which might be harsh for low level characters with crummy saves. I ran the adventure with Dragon Warriors characters around level 2 or 3, but I gave them a small squad of soldiers for backup and pretty much completely rewrote the tomb part of the adventure, so it isn't really a valid comparison.