Hey. I was interested in being LPI certified and I came upon this study guide which i feel can be used also as a learning guide to Linux. it's from www.linuxit.com
http://www.reggaetoneroz.com/SerNet-LATM-LPI-101-v-0.2.pdf
http://www.reggaetoneroz.com/SerNet-LATM-LPI-101-v-0.2.pdf