Kim, got a lot of good tips at the "go say hi" classes. I almost always carry little bits of chicken/turkey franks with me, to get Chloe's attention when she won't respond. Works 99% of the time..../forums/images/%%GRAEMLIN_URL%%/thumbup2.gif
Maybe an obedience refresher course for him. That and a bag of Pupperoni. Even though I know once on a scent, most beagles go deaf and not even food will get them off a scent espacially after they see the rabbit.
I would suggest a leash that wraps around your wrist or clips to your belt.
With Summer, It is always looped around my wrist, and I have a way of holding it so that if she does make a run for it, the leash tightens around my hand. It can hurt, but she isn't getting away.