Nice to hear from you and I understand your problem starting a Bloodhound for Trailing work.
Let me make a couple of remarks before I get to your question. You mentioned you have a pup.How old? I start my dog with some obedience work anytime after 8 weeks such as. "Come", "Sit","Stay" what "No" means and also the command "leave it". Usually this gives you the tools to control a large dog. The earlier it's taught the easier it will become.
You don't want a timid bloodhound nor do you want an over aggressive bloodhound. Look at this very carefully in hounds.
It is just as important that the handler understands scent and scent discrimination as it is to teach the dog to TRAIL.
You ask the difference between tracking and trailing. Tracking acutally is following the person or animal footstep by footstep which is far to slow to use in criminal cases or resue work. It is fine for finding evidence.
Trailing-- first the dog has to be a scent discriminating dog. Meaningit will take one scent it has been given (a scent article) and only run that scent and NOT SWITCH TO ANY OTHER. The dog then can take that scent off the ground, off vegetation,or out of the air and run the one scent excluding all others to find his object. Bloodhounds and labs do a very good job at trailing.
You can look at my Web site where I have listed several of my books that could help you.
"The Police Textbook for Dog Handlers", "Silent Witness","Manhunters". Prices are listed but I would have to have and address before I can tell you the shipping cost. I also need US currency, Money order etc.