I have motivation issues, too. Sometimes they have been so severe that I looked into avolition. I also have difficulty finishing things that I start, I have many video games that I have given up on, books, chores, anything that can take too long I can lose motivation to continue with. With chores, I have to find a reason to accomplish it, and usually it is other-based, I complete the task for another person. Unless it is health related, in which case I eventually find the willpower to take care of it before it bothers me more than I can handle (such as chores that would clear up my allergies). I have a high tolerance for suffering, though, so even then it can be tough to force myself to do something.
Desire itself I have not been able to locate. I only know that I won't see something finished unless I finish it. If I don't move toward what I lack motivation to do, it will never get done. I have to remember that I often feel better if I just act, rather than procrastinate till I find the willpower/want. I wish I had real tips for you, but I'm only beginning to help myself with this through the use of scheduling. It doesn't add desire but I'm more reliable to myself. I have scheduled myself into finishing a video game before! (Two or three hours a day until it is done.) I tried to schedule in painting/drawing but that hasn't held together yet.
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Let us comfort each other, and move tenderly when we are able. Let us hold hands and walk bravely, or fearfully together; for as long as there is Love, there is Hope, that everything will be okay, including the things we say are not.