What Dr1Driver and Pettit had to say is good advice. I'm an instructor at our field and I see pilots with your problem all them time, and there is one thing you can do to fix it. Practice, practice, and practice. I know that sounds like I'm preaching, but you would be suprised. The only thing seperating a pilot that just soloed and one that can hit the same spot on the runway every time is practice. I recommend to pilots that I've soloed to go out and do nothing but touch and go's for at least a tank of fuel every trip to the field, if not more. I promise that if you do this in no time at all you'll be nailing your landings each and every time. Trust me on this

Hope this helps

Ken