Not online but Fifty-four Devils is a great guide, especially for beginners. He used to have an online presence but I think he took down his stuff after the book was published. Worth a look and affordable.
https://www.amazon.com/Fifty-four-Devils-Folklore-Fortune-telling-Playing/dp/1491225785/
I use mine mostly without the book but sometimes the book helps. I bought this on Amazon to use solely without the book (book is weird anyway). Spiral Oracle Cards with... https://www.amazon.com/dp/B094JKW7N1?ref=ppx_pop_mob_ap_share
I learned from this older book Fortune Telling with Playing Cards by Sophia (1999 was 22 years ago?? I'm getting old). I paired the meanings down to a few words so I would remember the whole thing, printed/cut out/taped it to a set of cards. This way I can see what's reversed, also. I don't know if anyone else would like my system, but it works for me.
Very late to this, sorry, but no, Petit Etteilla isn't a Lenormand. Have you seen the cards? They are essentially just 32 playing cards, with upright and reversed meanings written on them, as well as "keywords" specific to their various placements in a slightly convoluted, but fun, series of spreads. 🙂
Lenormand cards, of which there are 36, do often, but not always, have playing cards insets on them, but are mainly identified by the standard pictures they bear. The meanings don't match those of the corresponding playing card in P.E. Also, the traditional methods of reading Lenormand are not the same as those for P.E., although there's nothing to stop one reading P.E. as one would read Lenormand.
P.E. is published by Grimaud and you can find copies on eBay most of the time. There's one on there now, from France. And naturally, they are available from Amazon France ( https://www.amazon.fr/France-Cartes-Grimaud-Etteilla-Cartomancie/dp/B00005QQZ9), and at a much more reasonable price! "AquariusWellbeing" on Etsy (not affliated) sells their own English language versions of the deck. Apart from the fact that they've augmented some of the meanings, rather than simply translating the word/s on the cards, they look quite nice.
Good luck with your search! I'd love to hear how you get on.