I kinda get that same way to, i have my beetle and my bus end to end in our garage and if i go in there to do somthing (even non car related) i usualy end up working on some little item of one of the cars.
Right now im not having to much of a problem getting motiveated, i recently started working at a shop that deals with restoring and working on german cars (mainly early 911's and 356's, some other makes and models to) and every day when i go in i get all amped up... its like going to a car show every day
i love it! after seeing other project geting done and worked on, it makes me want to go home (or do stuff in the shop) and work on my super.
one other thing to get things moving for me is to just order parts so you have somthing to do. but for me, that can prove to be dificult as i dont have a lot of money to spend.
Keep on keepin on! done give up... never stand down!