The page for Hombre is here by the way -
http://wiki.abime.net/file_transfer/hombreAs for a controller, you can use any Sega Master System or MegaDrive or Atari compatible joystick or control pad if you can't find a Competition Pro.
The Scart cable would definitely be your best option if you can find the correct Amiga RGB-Scart cable online.
You may also want to clean the floppy drive out before you put any disks through it or you could have heaps of read errors from scum built up on the drive heads. You can get floppy drive cleaning kits on eBay too, they look like a floppy disk with a cleaning pad inside of them instead of the magnetic disc media.
If anyone is wondering about the Playstation to Amiga/CD32 adapters they should email Nathan at AmigaManiac.com asking him when they'll be out, let him know there's a demand for these things.
