I can't say I know a lot about Channeling or Channelers, I am aware of three, however there are most probably a ton more.
Abe Heads is the affectionate term for those that study the teachings of
Abraham who is channeled by Esther Hicks and assisted by her husband Jerry on her recordings and in her travels. (Those that saw 'The Secret' caught some of Esther/Abraham)
Ramtha is channeled by JZ Knight, if you caught "What the Bleep Do We Know", that was a Ramtha production.
And then folks have told me about, but I haven't read any or seen any
Seth stuff as channeled by Jane Roberts.
All of it is often characterized and shuffled off as new agey charlatan garbage. However I find these three with all their detractors have similar stories and similar benefits to those that study, read, practice some of the techniques and processes. All three of them have had their share of star power and motivational gurus who have traveled in their circles and are now on the conventional circuits raising funds for public television and the like.
As I indicated it is my feeling that in any other day and time these folks would be called prophets...and as prophets they reject the possibility that they are connecting with source so they have protected themselves by making up an entity and not indicating they themselves are in contact but instead channelling....that is my current crutch that allows me to listen without discounting completely....over the years I've seen a lot of the stuff I said "yeah right" to become something I know is true so I tend to be more open minded. Of course the Ram says people are living in the center of the earth and in Mars, and Abe says they are from our galaxy different universe/dimension so....I still have issues. But I find much of the thought and information interesting, intriguing and with value.