I've just started agility with my puppy (2 weeks ago). As far as the tunnel is concered, the ducting is a great idea. My boyfriend installed our aircon only a few months ago and had some left. I've been using that and I have to say it works a bit too well. After about 2 minutes she decided that she loves going through it and my problem now is teaching her to go through ONLY when I ask her. You have to tape up the ends well as you don't want him/her to get to the insulation.
My jumps & weavers aren't as impressive as all of yours - a piece of pvc pipe on two plastic pots and bamboo stakes for the weavers (my boyfriend actually let me poke holes in his lawn - the dog has him wrapped around her little finger). Works well enough and after 2 weeks I'm increadibly impressed at how quickly she's picked everything up - she can do 12 weaves quite fast with maybe one mistake in every 10 attempts. She loves it!!!!
Oh and my boyfriends way of teaching her to go through the tunnel was to put it in the sliding door with her outside and us inside.