Strange to compare Warren Buffet to retail traders. You may as well compared steak to hot dogs...seriously. By the way, Mr. Buffet does do private online conference (chat) with his board members but that's not a fair comparison to typical retail chat room now is it.
Go to IRC to the financial server, Othernet server, Freenode server and many more types of servers. Once you arrive to a server, just type the command line /list. You'll be able to find at least 30+ active chat rooms and hopefully one of them with involve whatever it is you're trading. Some are well moderated so don't show up and cause trouble because they ban in a heart-beat. Also, talk to Baron (ET owner) and try to convince him to bring back ET chat room. It was a big problem a long time ago (problematic members) and he got rid of it because it was too much of a pain in the butt to maintain. If nothing appeals to you...start your own free chat room for you and a few online trading buddies you already exchange messages with at any forum you're a member. You may be interested in trying twitter or stocktwits too. Lots of retail and institutional traders use such but not for trade recommendations. In fact, I don't recommend using chat rooms or any other type of social network for trade recommendations.
Unless you believe a specific person has something to teach you that will help you to eventually cobble together your own methodolgy, chating about trading not only doesn't help it hurts. Those who say humans are a social animal are correct but it is unnecessary to socialize all day, every day. Trading is more like writing an endless novel than being a head waiter or financial advisor. By and large I don't mind the solitude during RTH but what I do mind is that, particularly for a scalper in less liquid intruments (CL, as an example), good strategies are best kept close to the vest and, every once in a while, I would like a knowledgable trader to be impressed as I talked about how I doped it out -- sure it's ego but that is human as well. I'm not talking about just the setup itself but the conditions it trades best in, the conditions that dictate taking a chance of it running away but still insisting on a second entry or even, god forbide, when to chase a bit and look for the bigger target. But to take in opinions during RTH (I only trade RTH) is, to me, nothing short of lunacy. It's not just that I don't care what others think ... I do care. I care that they never express it to me. I'm attempting to faithfully trade my plan every day and I sincerely wish them well trading theirs!!!
Oh yeah, I forgot about those famous daytraders.... By the way let's say they have a chatroom for the rich, would you know about it?
Most traders that actually use free chat rooms are not looking to be taught anything in reference to what you've implied. In fact, the few that attempt to use free chat rooms as such are quickly disenchanted and quickly leave after discovering that other users of the chat room do not want to spend their time teaching another user of the chat room the art of trading. Simply, it never gets to the point that it hurts. Further, the "teaching" (as in being mentored) chat rooms out there are not free. My point is that the OP asked about free chat rooms and wanting to know whom are key traders in those chat rooms. I don't think the OP realizes there is a particular distinction with free chat rooms when you sit down and compare them to fee-base chat rooms. Yeah, there's some free chat rooms out there where users share trading tips, talk generally about the markets but a majority of them are either talking off topic or "ghost towns" with about a dozen users not saying a single word. The latter is very odd but common place. The key is to know what you want before you arrive to any free chat room. If you're looking to talk about the markets "in between" trades, general market discussions, off topic discussions or as a real-time help group...they can be very useful for such. For example of the latter, I once ran chat room for TradeStation users on IRC when Omega Research changed its name to TradeStation (about 135 users). Later, I was a member of a CQG chat room on IRC (about 47 users)... The chat rooms were very useful and users got immediate (almost real-time) answers or help to how to use these particular software from other veteran users of the software. I've also been a member of chat rooms where users discussed global economic issues by users from many different countries. Yeah, once in awhile someone new showed up and asked for example is Gold GC a buy now. Usually that trader got no replies or someone replies and say you're in the wrong chat room or please read the topic header. Thus, if you know exactly what you're looking for and use it appropriately, free chat rooms are extremely useful. Gotta know what you're looking for before entering any chat room because if you're trying to use a chat room for something its not designed for...you'll be greatly disappointed. Therefore, if you're a trader that's looking for someone to feed you buy/sell signals, teach you how to trade...you ain't gonna find it in free chat rooms. Meant, you may find it in a few free chat rooms out there but the content won't be useful and you'll quickly move on to something else before the chat room does you any harm.