I'm another bread machine user but I made bread by hand for years and years. The bread machine makes it much easier (I don't have to plan my day around punching down dough) -- if you've considered one, go for it.
If you do want to learn how to make good bread dough, allrecipes.com has good tutorials on bread making (I've used their bagel tutorial). Check their site and you may find what your errors have been.
Are you checking to make sure your water isn't too hot/cold? Use a thermometer at first to get a good feel for that. Are you proofing your yeast (letting it sit in the warm water and begin to foam before adding it to your recipe)? This helps you know whether your yeast is good or killed by your water temperature .... No-knead breads often have different tastes/textures than a standard recipe which may be affecting things for you.
You may be adding too much flour - bread dough should be relatively sticky especially the no-knead ones (quite liquid in my experience even). Even when making standard doughs by hand, you want a dough which is smooth and silky on the outside, but not dry or rough. Knead in a little flour, not a lot. When they say, "like a baby's butt" they mean it!

Are you trying to make mostly whole-grain breads? I honestly think it helps to learn with a white-bread type recipe selection before moving on to whole grain breads .... it takes a more deft hand to do whole grain breads so that they aren't too dense etc.
Where are you getting your recipes? A good all-round recipe book for baking is the King Arthur flour one - I have an old Pillsbury baking cookbook that I use sometimes, and for whole grain breads, the
Laurel's Kitchen Bread Book is lovely. There are some really good bread books out there.