Below is a link to some interesting review papers on HPLC/LC systems. Well worth a read to help you better understand the topic. Explore more on your own by visiting pubmed.gov. Remember to use the filters on the left hand side of the page to help you narrow your searches.
Research papers are a great resource for learning. One of the largest databases of peer reviewed published research papers is housed by the US National Library of Medicine National Institutes of Health. You can find specific papers on techniques or new discoveries or review papers which offer a broad look at a particular topic. This should be your first stop for research on topics we’re discussing in lectures or for your assignments.