I think they make you pay, or have some kinda deal on a game, but most of them I've looked at are always offline or play once a month online.
titled players who accept challenges from low ranked players
I like to accept challenges on live chess from any player, so long as its unrated and around 3-15 minutes. I don't play correspondence though.
WFM Monika Gedvilaite [http://www.chess.com/members/view/monika84] chose some days ago 2 players under 18 from her group to play a correspondence game against them for free (and advise them, too, afaik)
(i hear very good words about her coaching, btw)
I've seen a GM play low-rated players, but he offered draws or resigned all of his last online games here :/ (he told me it was a useless time expenditure for him)
http://www.chess.com/echess/game?id=105301762
IM Chessexplained is a good choice.He doesn't see the rating.He's around 2300+ but will explain you a lot during the game but you just have to be bold enough to ask him.I have played against him and he has explained me a lot.
You can find him here.He will only ACCEPT YOUR CHALLENGE IF HE HAS A LESS NUMBER OF GAMES (AROUND 50).Good Luck
http://www.chess.com/members/view/Chessexplained
I challenged about 10 titled players and only one accepted a daily game challenge sometimes if you go on open challenges on chess.com some titled players might be offering a game
Does anyone know of any active chess.com members who are titled and accept challenges from lower ranked players? I am currently around a 1450 in correspondence and I would like to play against a lower rated master (1900-2000). I think it would prove a valuable game to analyze and challenge me to thouroughly study each position during the game. Anyone know if such a player exists on the site?