Hi Wayne,
Welcome to AH, great site. With regards to you hunting in SA, I would definitely say don't worry about being a greenhorn, and look at the animals that you would really like to shoot, and then have an open discussion with the PH/ Outfitter.
Myself being a PH, i have had many greenhorns come out and hunt, and very experienced hunters and both have had just as successful hunts. I always guide the hunt according to the client. Thats why i say, go for what you want, and the PH will assist in you in getting the trophies of you want! Also I agree, practising with sticks is a good idea, we use sticks, and find that it is very useful.
Enjoy the experience!
Kelvin milsom