I'll post about this with a bit more depth with numbers from another month or two.
So far here's what I have:
I put up
Saltwater Witch,
Seaborn, and
Sea Throne on Amazon.com, B&N (Nook), Apple iBooks, and Smashwords around the middle of March. Here we are 25 days into May-so roughly 9-10 weeks of sales, and I've sold almost 800 books.
Saltwater Witch has been hovering in and out of the Top 100 of "Bestsellers in Books > Fantasy > Magic & Wizards" at Amazon.com, which is pretty cool. All three books have been in the Top 100 in "Kindle Store > Books > Fiction > Fantasy > Contemporary" on Amazon.co.uk, getting down into the 40's. So not too bad.
Details when I get the time!
.