Ribs are not hard to do. Well really NONE of it is hard to do, you just need to find what works for you and then your set.
The main thing is getting to know your smoker and being able to reproduce your results. I suggest keeping a small "log" of your results. then each time you can always come back to them and reproduce the same result time and time again.
What works for me on Ribs... Pull the membrane on the bone side! Rub em up with my own stuff I mix up, then in the smoker it goes (200-225 degrees) spray with apple juice every 30 minutes, till the meat "pulls" (its like the meat shrinks and exposes the rib bone) This usually takes somewhere around three hours. Then foil them using heavy duty foil, and adding in a half cup of apple juice before sealing them up, then back in the smoker for two hours at the same temp. After the two hours remove them from the foil and if you like them "Wet" then slather with sauce and back in the smoker for a half hour to an hour. or if you like em dry... remove them from the foil and sprinkle with some more rub and then back in the smoker for the same half hour to an hour.
Keep in mind this is for Spare ribs, baby backs require less time.
Apple wood is good, as is most any fruit tree... we have peach, apple and cherry. I also use a lot of pecan.