Yes - it is frustrating! We've been through this once with our now six year old boy. After lots of different trials, none of which were successful, he finally announced to us "when I'm 3, I'll pee in the potty." Sure enough, on his 3rd birthday, he started! Poop was another matter completely. Nothing worked, he held it all day and then pooped in his pullup at home after pre-school - usually went to hide in his room. We did follow the advise of his pre-school teacher, who suggested that when we notice he needs to poop, to tell him that he needs to go into the bathroom to do that (still in his pull up, but at least he was in the right room!). He responded well to that, and around his 4th birthday (I KNOW -- it took a long time!!) I reminded him that we wouldn't be able to start kindergarten when he was five if he wasn't pooping in the potty. I told him he had a whole year to work on it. Well, that was the magic bullet for him! He was so excited about going to kindergarten that within 3 days, he was pooping in the potty! We were lucky to stumble onto that motivation for him. But - the key here is -- HE had to decide on the timing....HE had to decide he was ready. Not us.
We're now in the same process with our almost 3 year old boy. In general, I think boys are a bit slower to potty train. Neither one has EVER been bothered by a wet or dirty diaper --ever! I received some great parenting advise our first time around struggling with this...in all the "battles" or "power struggles" (or however you want to phrase it) in parenting toddlers/pre-schoolers, there are two issues you will ALWAYS lose in - what goes into their mouth, and how it comes back out! :) Once I realized and accepted that - meal times AND potty training become more tolerable. He'll figure it out -- just try to be matter of fact ("the bathroom is where we poop"), reward the behavior that you want to encourage, and don't make ANY negative reactions/comments when he poops else where. Just matter of factly state, "next time, honey, please go to the bathroom when you need to poop. It will happen eventually -- the trick is to stay patient and keep our cool in the meantime! Hang in there!! :)