Toyota Repair: toyota paseo, connecting rod bearings, crank shaft

Question
My friend was driving my car (oh, it's a '92 Toyota Paseo) and developed a steady knocking sound from one of the lifters.  He checked the oil level and said it was out of oil (which is impossible) however, the knocking sound is steady and not irratic and I was told that I might have thrown a load bearing and it was simple to replace.  I do not know how to do that, and if there is any damage to the crank shaft how do I go about smoothing it out without having it turned.  Or is it something simple that I might be over looking.  He did replace the oil in the car but that seemed to not do any good.  Any information would be appreciated.
Thank you very much,
scott.

Answer
It sounds like there is a problem with the connecting rod bearings because of a lack of lubrication, rod bearings are not simple to replace and there may be other damage to the engine, especially if the crankshaft is damaged.
Once the knocking noise has started there is major engine damage, instead of trying to repair this engine it may be more cost effective to just replace it with a used engine, or a remanufatured unit, the cost of repair may be more than the car is worth so think about that aspect before putting a lot of money into this.