I have been working on a commentary on the Psalms. I have decided to compile some of my favorite links that I discovered during my research. There is a mix of exegetical and sermonic links. Here is what I have for Psalm 18 (in no particular order). Feel free to mention any that you find helpful in the comments section.
Literary analysis of Psalm 18 – Covenant of the dynasty of David’s house: http://psalmsstudy.com/psalms-literary-analysis-by-chapter/literary-analysis-psalm-18-covenant-dynasty-davids-house
Analysis by C. J. Labuschagne: https://www.labuschagne.nl/ps018.pdf
William Barrick’s notes: https://drbarrick.org/files/studynotes/Psalms/Ps_018.pdf