I've stolen bone chips from Liches, so maybe u can steal from lower level skeletons as well... ...but buying a bone chip is the easiest and fastest way to go =)
Bone Chips can be obtained in any area with a bone monster. You just have to be lucky and hope they drop a bone chip. I'm from Windurst and get Bone Chips from Magicked Bone mobs in East Sarutabarta. I just usually sell them cause i don't need them. That's where you can obtain Bone Chips really easily
Not all that simple, you have to be like level 15 just to be able to defeat the Enchanted Skeletons. Then you also have to ensure the Goblins don't join in and you have to do it many times to make sure you get just one damn bone chip.