Assuming you want to stay a solo contractor, Alan Weiss' "Million Dollar Consulting" is a great book to read on this subject. It's written for soft-skill consul

Assuming you want to stay a solo contractor, Alan Weiss' "Million Dollar Consulting" is a great book to read on this subject. It's written for soft-skill consulting (management, HR, etc) but is highly applicable for developers and technical consultants too. His main angle is to shift towards "value based pricing" and becoming a true partner to your clients, focusing on producing business value (rather than code). This mode of thinking was a huge shift for me in how I thought about my work, choosing clients, and helped me get over that wall.