Can you be more specific as to which variations of the Sicilian defense you are interested in?
good sicikian books for advanced player

i like many i guesss it would depend on the book as i like the sicilian in general and then play the line from the book.

Ftacniks book is really good but at your level, you should be focusing on tactics so get a good tactics book instead.
You may memorize some line in the book but what will you do when your opponent takes you out of theory? Your left on your own to navigate the position and all the tactics and what not and knowing the theory won't help.
People will play a GM for a few moves and then bam, your instantaneous skill level will rapidly decrease as soon as someone takes you out of theory and your left wondering how to take advantage of the deviation (if you even can) and to do that you need good strategical skills as well.

I'm a big fan of the Najdorf, and these are the best Najdorf books (imo):
GM rep 7 The Sicilian by Ftacnik (wait till Dec though cause a revised edition is coming out)
The Sharpest Sicilian by Georgiev & Kolev
Play the Najdorf by Rizzitano
Cutting edge 2 6.Be3 (in Najdorf)
Experts on the Anti-Sicilian

Ftacnik most definitely, but I would advise to wait for 2nd edition in December because the 1st had a lot of missing lines, Quality Chess (the publisher) did release newsletters giving missing lines etc, but if you haven't bought the 1st edition already, then it makes a lot more sense to wait for 2nd edition.
I would also recommend Experts on the Anti Sicilian if you don't like the lines given by Ftacnik, I really loved Avrukh's chapter against The Grand Prix attack (2.Nc3), which has personally given me a lot of trouble in otb chess, not anymore though!
The other books I mentioned I bought to cover lines missing from Ftacnik's 1st edition book, specifically his response to 6.Bg5 where he gives 2 lines; 6... e6 7. f4 h6?! which is more ? imo, it's called the Browne variation and leads black into an endgame where he's a pawn down and fighting for a draw (not why I play the Najdorf). His other recommendation is 6... Nbd7, which is fine theoretically atm, but that might be due to not much analysis on it yet. I'm hoping that in the revised edition they'll drop the Browne variation and possibly give the: Gelfand variation, Poisones Pawn or simply the main line. Wait and see though.
well im not an advanced player, but i guess the sicilian gm repertoire, the one that lost tactic posted is pretty decent. I had a gm repertoire for white and when i used the lines against my chess program i had pretty easy to win situations. Ok i only played on level 1800 but i still think they are pretty good.
any ideas on some good books for black pieces on sicilian advanced level or club. thx