There are several freely available LinAlg books on the 'net as well. Well, counting pirate books, there are lots of them. But even limiting it to the legally available ones, there's quite a bit of learning material out there. For example:
https://www.math.ucdavis.edu/~linear/
or
http://joshua.smcvt.edu/linearalgebra/
This is also a handy resource to keep around:
https://people.math.gatech.edu/~cain/textbooks/onlinebooks.h...