Huh?
I was afraid of that... the problem is that this is not a simple issue. As you noted yourself, Charade's simple answer to your question didn't really pan out. That's because the issue is a lot more complex, and there is no simple answer -- at least not a positive one.
I'll try explaining myself a bit better...
There is no, and almost surely never will be any, official listing mapping QAM frequency assignments to cable channel assignments.
Okay, so this is basically a flat-out "No" to your question: You wanted a way to know what these channels are, and the answer is that there will never be an official list.
These assignments are dynamically changed, without notice,
Even if you take down the channels now, and make up your own list, it will only be valid for now. The channels could all change tomorrow. They do this to improve the quality and reliability of channels, moving them around to perhaps take advantage of pairing lower bandwidth channels with higher bandwidth channels, etc.
and cable boxes, CableCARDs and digital terminal adapters are notified through signaling specific to their operation.
Cable company-issued equipment have a separate way of keeping in touch with the latest changes to these assignments.
Televisions, such as your LCD, do not have the functionality necessary to receive that signaling.
Generally, televisions don't.
Generally, your local broadcast channels include PSIP data, which the cable company passes along to your television.
Everything I said above applies mostly to the cable channels. The local broadcast channels (ABC, NBC, CBS, etc.) may provide you
another way of dealing with this, but that will only help you tune in the local broadcast channels; it won't help you tune in the cable networks.
Many (though not all televisions) have the capability to use this PSIP data to map the QAM frequency assignment for local broadcast channels to their broadcast channel using this passed-through PSIP data.
Your television may or may not be able to use this information to help you.
However: (1) This only helps map broadcast local channels, like ABC, CBS, NBC, etc.;
This won't help you find ESPN, or CNN, or Discovery, or Disney, etc.
(2) It maps these QAM frequencies to their broadcast channel, i.e., 4-1, rather than their cable channel, i.e., 804;
The way this capability works is that instead of you worrying about what 49-102 or 79-18 (two of the channels you mentioned) are, you'd simply deal with the "friendly" channels that your local broadcast channels advertise. Perhaps your NBC station is "Channel 18". If so, then you can just enter 18-1, and you'll get "Channel 18" (even though it may really be on channel 49-102).
(3) It relies on the broadcast local channel including the PSIP data in the feed that they provide to the cable company;
Not all local broadcast channels tack the necessary data on to their broadcast signal to make this work (though they are required to by law, and, generally, when they don't, someone forced them to fix it quickly). Beyond that, even if they are doing what they're supposed to with the signal they are broadcasting from their over-the-air transmitter, they may be providing a completely separate feed of their programming to the cable companies and that separate feed may not have the right data tacked onto it to make this work.
(4) It relies on the cable company not screwing up the PSIP data;
Even when the local broadcast channel gets this right, there are a few things that the cable company can do to screw things up.
and (5) It relies on your television using the PSIP data correctly.
And even when the local broadcast channel does everything right, and the cable company does everything right, your television might not work correctly.
I hope this is a bit clearer.
Oh well, I guess I'll have to keep a pen and paper down there to write them down as I figure them out. 
