http://bowfinprintworks.com/SansIDPage.html
http://bowfinprintworks.com/SerifGuide/intro.php

The Bauhaus guide on this site just helped me find a font I haven't been able to identify for a week. One the other hand, I honestly cannot figure out how to use the sans id table guide. I've read through the instructions several times, but it won't penetrate my brain.

Thanks Riccard.
Not exactly what I was looking for, but that is a nice resource to have.
I'm pretty surprised that something like I described doesn't exist, it would be be quite helpful and an excellent teaching aid as well.

There's also:
http://www.identifont.com/
http://typenav.fontshop.com/

When you get used to using these kind of sites, eventually you'll be able to do the things you described by memory.

@Plaidjaney - There is a more user-friendly beta version of the Sans ID Guide that works like the Serif Guide, but at the moment my site is down, and I can't get you the link.

- Mike Yanega

My site is back up. Here is the interactive beta version of the Sans Serif ID Guide.

It has been brought up to date through the most recent FontShop FontBook (2006), but relatively few updates since then. Images are still missing for many of the newer fonts, and designer information is still missing in many cases. Jan has generously volunteered to help bring it up to date, and eventually it will replace the static Sans Guide now on my site.

- Mike Yanega

BTW Brian, the old book "Rookledge's International Typefinder" has a diagnostic visual key scheme to use attributes of letters to identify typefaces with those features. It's excellent, but it was published in 1983, so the typefaces are truly 'classic', and many have not made it into digital form. The collection of Serif fonts in my edition reaches 240 typefaces. I think these is a later edition of the book, but still with fewer than 300 serif families shown. There are only 50 Sans Serif families in the next section of the book, although more are found under Display headings.

Identifont does try to use a similar scheme allowing you to select attributes for a subset of letters, but I have found it very unreliable about using the information you give it, as if some of the algorithm code is messed up. Many times the selections are not even close to your choices.

My Serif and Sans Guides use a limited set of Key letters for you to select structural attributes, and tries to show you all the catalogued fonts that have those attributes for the letters you specified. You use the visual comparisons to pick the right font from the choices shown.

- Mike Yanega