Get a rack of spare ribs, they're less expensive than baby backs. Make sure you have an accurate chamber temp reading for the smoker and maintain 225*.
As Pineywoods has pointed out, put your ribs on for 3 hours.
After 3 hours, pull them and double wrap in foil with a half cup or so of apple juice or liquid of your choice, tightly seal the foil and put back in the smoker for 2 hours. (I prefer 1 1/4 to 1 1/2 hours)
After 2 hours in foil, pull and unwrap, remove from foil, place back in the smoker for 1 hour to firm them back up. If you want to sauce the ribs, do it during the last half hour of the smoke.
After 1 hour, pull the ribs from the smoker, tent with foil or wrap again in foil and let them rest 1/2 hour on the kitchen counter.
If you follow the 3-2-1 (for spares) I don't know how you could end up with shoe leather...the foiling phase alone will cause the meat to nearly fall off the bone.
The biggest bit of advice I'd give is, NEVER give up!! If you can smoke a butt, you can smoke some great ribs! Calibrate your thermometer you're going to use to monitor the chamber temp to make sure it is accurate.