Cal Newport has written a great piece on a process for getting things of a creative nature done when there are other demands on your time. I recommend reading it here.
His ideas draw from those of Paul Graham and David Allen and basically revolve around scheduling blocks of time through the week to do the creative work (1 to 3 hour blocks) and scheduling everything else around those like they were locked in appointments. Read Cal’s full article to get the full richness of this.