I have a simplified version Jazzman's setup. I record guitar using an Apogee Jam and vocals using the Rode NT USB (essentially a NT1-A with a built in ADC) and am also using Garage Band on a MacBook Pro. At this point I am tracking any midi using the laptop keyboard... which isn't great but at least gets something that I can work with.
I do have access to a full digital piano with midi out but don't currently have a midi cable (should rectify that). I've also built a load box so I can record my amps directly but it isn't working properly and I haven't had time to debug it so at the moment I'm going straight in with the guitar and using built in amps in Garage Band.
Regarding my workflow... it isn't really bedded down but I do my composition in Garage Band (need to try iReal). I start offline and work out a part of the song, usually just chord changes and basic melody. Then I use the built in drummers to find a groove and lay down a very rough take of the progression. I'll then use the Master track to lay out the overall shape of the song (intro, verse, chorus, verse... etc.) and fill in the rough shape of each, including a very rough vocal take, which I just do on my laptop mic so that I don't need to set anything up. I muck around with key and structure at this stage until I'm pretty much happy. Then I go back and start recording proper takes of each track, starting with any midi work, then bass, rhythm guitar, vocals, lead guitar and finally details and embellishment.
I will say that recently I've only really recorded for challenges so I don't agonise over the perfect take and once a track is down I tend to live with it. I suspect that if I were trying to do something worth publishing I would be a lot more fastidious.