I've discovered NovelRank and am kind of addicted.
I'm one of those people who is always uber-curious to know how my book is selling. Some of my publishers are too sweet and send an itemized list of exactly how many copies sold at each vendor when they hand out royalties. Some publishers are a bit more general: you sold this many this quarter, here's your money.
But impatient me, I wanna know now...and I wanna know every detail. So, I would haunt all the vendor sites.
-On All Romance Ebooks, if I looked up my name in the author search, then organized or "showed" them by bestseller, I could tell something had sold every time the order changed.
-On Fictionwise (yet another vendor place that sells some of my ebooks), I do the same thing. Look up my name, then display them in order of bestseller. Fictionwise usually only updates once a week (on Mondays), so I don't daily check them.
On Amazon and Barnes and Noble (yeah, you think I have a serious problem by now, don't you?!), you can look up each book and look at your "sales rank." If you don't have a sales rank or if it's blank, then your story hasn't sold there yet. BUT...if you do have rank, you've sold at least one. Each time you sell a copy, your ranking number goes down, and then it climbs right back up...until you sell another copy. So, every times you check and the ranking is lower than it was the last time you checked, you sold a book there. I know, cool, huh.
That's how I kept track of my Amazon sells for forever until I learned about NovelRank. You just give them the URL for your book on Amazon and they keep track of each sale for you. Now I don't have to guess how many books I've sold on Amazon.
Isn't that amazing? Well, I think it's totally cool. And seriously, I don't believe I'm the only curious author who wants to constantly know how many of my books have sold because I've looked up other authors' books on NovelRank and found their books too!
There's my curious author tid-bit for the day. For those who already knew, well...sorry. That's all I got for now!
Disclaimer: Tracking your books sales can become a bad addiction and can lead to loss of having a social life plus you might spend so much time tracking, you never get back to work on your current WIP. Proceed at your own risk.