Our community has created quite some useful repositories of MSX information of its own, such as Generation-MSX for screenshots, cover images, cheats and all sorts of other information, MSX Solutions for detailed walkthroughs and maps, CheatMSX for various cheats, and of course our very own MSX Wiki.
However, KdL recently brought to our attention that one of the biggest and well-known game information archives, GameFAQs.com, also has quite an extensive overview of MSX games in their database.
On this overview page you can easily get to the cheats, reviews, FAQs, images, and message boards for each of the games they have listed, or use their system to indicate which of the games you own.
Relevant link: MSX Cheats, Reviews, FAQs and more at GameFAQs