Is there a way to find out which skill books my character has read?I have read 76 of them and i want to read all 90

Probably with a PC, but not on consoles.

I always keep the skill books I've read, for every character. Even made up a checklist to printout for new characters. Only thing I can say if you havn't been keeping track is to use the UESP to find the books and try reading them, as already read ones do not give another skill. Just keep track with Notepad, or keep the book, and you'll eventually figure them out.