When I graduated from business school I gave a few friends a copy of a book that meant a lot to me – Brenda Ueland's If You Want To Write.  It was given to me in college and I still have that beaten up copy of inspiration on my bookshelf.  See below for a quote from Ueland.  Buy it here.

“I learned… that inspiration does not come like a bolt, nor is it kinetic, energetic, striving, but it comes to us slowly and quietly and all the time, though we must regularly and every day give it a little chance to start flowing, prime it with a little solitude and idleness.”
Brenda Ueland