Agreed it would be nice to be able to find this info in-game. But for now we have to rely on external sources such as: https://eddb.io/station
As appreciative as I am of everyone who has provided a third party app (eddb, coriolis, inara etc), pretty much ALL of this stuff needs to be in the game. It's absurd that I have to basically have a second screen just to find things.
While I'd appreciate a search function for several things, as far as modules themselves go, I never had a problem finding anything (Even before I was able to use Shinrarta). Just filter your map for High-tech systems with more than 20M population, and you'll find everything. Any if they don't have just that one module you're after, the second such system will, 100%
Someone said somewhere else that it would be great to be able to access the Market, Outfitting and Shipyard via System map, and I agree with that. But the truth is, an hour or two with a paper and pen and a bit of research and you'll be able to tell the commodities and outfitting by feel.