The entire four-book series, plus all of the side stories are now available as a two volume set with five new color illustrations, here:
THE ALICORN ADVENTURES

Yay! I'm actually working on my own book after being fired from my job, so I can't spare the expense right now, but as soon as I have disposable income again, I'll be adding this to my collection right alongside the old volumes. I'm glad to see these available again!

Yes, I have a financially unwise habit of purchasing multiple editions of the same books.

I currently don't need enough books from them (just these and Time Loop) to make it really financially attractive to buy them right now, but I'll definitely pick it up at either whatever next convention (probably/hopefully GalaCon 2022?) or I'll just pay the shipping plus what will be a lot of taxes (but relatively way less) once I can order at least ~6 books at once.

It would also mean ending up with four "versions" of The Celestia Code, lol. (I have three of the Lulu ones, and all three have a different font).