Aetherpedia's the closest one, but, an important notation is that information isn't free. The Matrix is all about sequestering, like the old AOL days. If you want information about, say, the St Louis Slammers, you can use a NeoNET account to go to the official repository of all things Smashers .... because ethat information isn't legal on any other network unless they pay NeoNET a fee. The public Matrix can go have a look, but you'll have to slot a fee to do so.
Adding to what Waakshaani said...
Keep in mind that (not to get too real) there was never anything like Net Neutrality in Shadowrun. The grids are allowed to blatantly favor and block information, which is why everyone who can afford their own grid has one (so, just the megas and local governments). If you're on the Seattle Emerald Grid, you see what the people running the grid want you to see. So,
propaganda "news" about what they want you to think, advertisements from whomever paid them the most (the matrix may be infinite, but AROs still have a limited amount of space in your view, gotta pay the premium to be the most visible), and of course the most obvious hosts in the "sky" are the ones who're paying the most to be there.
So, if any kind of free-to-access matrix encyclopedia existed, it would be basically impossible to find on any grid. It of course would still cost money (you do have to pay regularly for hosts bought legally) but wouldn't be able to drum up enough cash to sustain itself. And that's before we even get into the reality of competitors sabotaging it so you have to go to them (and pay them) for information instead.
JackPoint is such a big deal because of all that. It doesn't let people freely enter, but once you're in you don't pay. It's an illegal host, so the upkeep is done manually, not through nuyen. And the information available on it is freely available to anyone on JackPoint because it saves lives.
Information has never been free in Shadowrun, that's part of the cyberpunk setting, with hackers being the data rebels who think information should be free (within reason-- the work to assemble said information ain't free). Every rule book (like, literally) is set in that frame, of being someone's free-access upload to JackPoint. Some parts are stolen by a hacker for JackPoint, some parts are written personally by members for JackPoint, some parts are commercial information being donated for free in order for that person to gain access, etc.
