A potted history of Cartographer's Craft:
As anyone watching me flail on Tumblr will have noticed, one of my favourite things about being a latecomer to fandom (relatively speaking) is piecing textual histories together. It's like medieval lit without the palaeography or codicology! Sam's work is particularly fun because the great journal hack of 08 means some of the "primary" evidence is actually reconstructions.
Lo, then, this is the history of Cartographer's Craft, pieced together from kayloulee's History Of Things Inept Missed In Potter Fandom, my own research, and testimony from the man himself:
Somewhere in late 04 or early 05 versions of the early chapters were posted. After the release of HBP they were systematically edited for canon-compliance, with new versions posted over about a week from 22nd June 05. The non-compliant versions are lost to the mists of time. The LJ posts from after the HBP release still survive, with their comments, and where one can discover that the fic was originally rated a mere PG.
Tumblr user darlinggirlpicklock added the data that the fic was originally finished somewhere in the holiday season 05-06, probably at christmas or new year. This means we're up on the 10-year anniversary now, so... happy ten year anniversary, Cartographer's Craft, I made you 1/4 of a podfic!
Some time after the great journal hack of 08, when Sam lost the corresponding posts on his personal journal, the text was moved to Dreamwidth, which is where I met it. The author's notes to ch 1 at Dreamwidth give some idea of the revision history, which doesn't appear on the A03 version (more details can be gleaned from the comments on the LJ versions of chs 1-6).
It's not evident from the post-HBP LJ posts where the transition between "revised version" and "written after HBP" is, but my money is on Chapter Six as the first entirely new chapter Sam wrote after reading HPB - that's the chapter where RAB is identified and the locket found. The chief change during revision was removing Snape from the early Order meetings; minor fixes included altering the relationship progression for Remus and Tonks, and adjusting the Harry/Ginny context. Some tantalising references in the comments on the now-compliant version's LJ posts suggest Harry may have once had a crush on Bill Weasley - that shows up later in the fic as a vague attraction but not exactly a plot point.
At some point, someone did make a podfic of at least part of Cartographer's Craft: both Sam and Kayloulee have told me it once existed and is now lost. I'm pretty sure it was lost by 2010, when I discovered the podfic of Stealing Harry: if there'd been a podfic of Cartographer's Craft I'd have gone straight on to that.
Sections of Cartographer's Craft deal with the non-existent book 'Animagus Winter', which eventually turned into Sam Starbuck's original novel Nameless, which is an excellent read in its own right. There's a post from 2014 at Sam's Wordpress Blog entitled "The Book that Saved My Life", which talks about that process.