Better late than never I've been having a read. It's really good. It's also very @First Age in its themes and approach. It's uncanny how well it suits a bit of fantasy setting writing I've been playing with. Top stuff. I may grab it in print.
Online gaming comes in several flavours. There's text based play-by-forum games similar to old style play-by-post games. There are browser based games that use a server like Roll20 to host the game and the GM runs the game via that. There's Fantasy Grounds which uses a similar back end server to host games but mostly requires payment by somebody to run the game and sometimes from players.
The one I've used the most is to have a Google Hangouts session to get the group together and everyone logs in and sees the other players and the GM who then all narrate what they are doing. Various die rollers and varying handout display methods work fine with this.
I've played a four year playtest of a GUMSHOE game and a couple of years of Night's Black Agents as well as shorter games of things like One Ring, Esoterrorists and Yggdrasil and am just starting to play in a game of Masks of Nyarlathotep which I expect to take a couple of years playing around twice a month for a couple of hours at a time.
However Google Hangouts is going away as a public offering sometime in September so we'll most likely go to Discord which has both a text interface and video.
At a minimum you'll need a decent camera, decent microphone, and to avoid feedback, a headset as well as decent broadband speeds to cope with the video and audio streams. A reasonably up to date PC or laptop should have enough processing power to deal with the stream, a modern Chromebook or similar works for some of the people I game with.
Sorry if I've caused confusion. After another recent thread, I thought I'd try thread Necromancy.
As for online games... Usually for me it's a straight Hangout and relying on player trust for dice rolls (extra tech options *can* get in the way for me in a game). Most laptops will be good enough, and have a built in webcam, but you will as Nigel says probably need a headset or similar. But you will need a good home broadband speed; that's the pinch point.
Roll20 is another popular choice and does integrate dice rolling and such things as sharing of documents. I've also played voice only over the Tavern Discord; I usually prefer to have video for something closer to the face to face experience but the voice Discord works.
The main issue with Voice Only games is overtalking the other people. When you have no visual cues it's all too easy to interrupt folks when both of you try to talk at the same time. Stick with audio and visual to make things easy.
My group play using Roll20 for the tabletop and Discord for video. Roll20 sort-of has support for a variety of systems: we've used FAE and Feng Shui 2, and it's been ok but not excellent. Don't bother with A/V in Roll20.
The peer-to-peer audio/video is pretty lousy in Roll20 and has been since Google broke the integration with Hangouts by removing their APIs. I'd definitely go with Discord and even Hangouts (while you can) rather than the built-in Roll20 stuff.