This is the third time I have killed the wall of flesh and it's given me sweet drops but never given me the pwnhammer. So I'm stuck there until I get it, any suggestions?
This hammer has a 100% drop rate. Some people have reported a bug where it does not drop (and I have my theories as to why this is but since this is not a post about that, lets move on).
The Hardmode ores are not required for top tier gear any longer.. they are not tied into the progression so this really is not that big of a deal. Use the shops (The mushroom spear is ungodly for example) or events (A cutlass is very nice as well as frost armor from defeating the ice golem things during snow storms) to gear up. Then go and destroy the Destroyer of Worlds (He is still super easy to kill). He will drop Hallowed Bars directly and then you can move forward.
So, as you can see, you are not stuck. You just have to forego using those three ores and lets face it, there is no real need to use them except for building blocks.