OK. Question #2. Do you really have to build it yourself? Putting together something so powerful to drive possibly delicate electronics.. You need some experience to do this. And you wouldn't be asking this question if you were an electronics guru I think..
Your local friendly electronics shop will sell you a power supply to fit your requirements. Ask for 24V - this is more common and will work just fine. Or you can buy online.. Something that powerful will cost you though.
If the connector doesn't fit, use a knife and some duct tape to replace it. Or solder something somewhere.