Do it yourself

Well my wife has been asking about a pool for over a year now. A friend of a friend was going to remove a 24'x48" pool from his yard. He offered it to us as long as we helped build a deck. After we pulled the liner out the steel walls and frame was rusted really bad. I still have the pump, filter, all the tools and the ladder. I am thinking of building a pool just not an above ground. I am thinking of digging down 3' and building an above ground part that would be also 3' out of those stackable landscaping stones. I know the back side of those are rough so I would use morter to smooth it out and then put some indstural felt to protect the liner. I have even thought of making the entire pool in the ground and making the sides out of cinder blocks and the bottom would be sand. Then I would get a custom fitting liner. I know this will not be a simple project but after I finish the kitchen/dining room this is something I am considering. I really hate to spend the money and have an above ground pool because they are not even close to 6' deep. Anybody ever built their own pool? Anybody ever build one half above and half in ground? Any thoughts would be greatly appreciated.