How do I release space in hard drive???

I have win 7 in a bootcamp partition (apple macbookpro). I define 60 gb to the windows... I only have 3dmax, sony vegas, autocal lt 2008 and my hard drive it's full... i don't have any kind of documents or projects... it's everything in external drives... Can i install or make something to release space?? I already clean with ccleaner and the normal clean from windows... thanks