That power supply seems fine. It has a current limiter BUT the display resolution is 1ma meaning that for any current between 0.5ma and 1.5ma its going to read 1ma. Thats woefully inadequate so you can't rely on the display. Adjust the current setting using your DVMM.
If you're using the current limiter (Colloidal Silver), set the power supply voltage to be maybe 5-10V higher than your desired cell voltage to cover the current limiters headroom requirement (if there is any) and to give the current limiter some breathing room beyond this so it can adapt to changing load to still keep the current constant.
For copper wire, a piece of telephone cross-connect wire or a piece of wire out of a CAT 3,4,5,6 (think there's CAT6 now) ethernet cable or any similar thing where the wire is around 22-24 gauge will work nicely.
The reason I and others are starting to use such thin wire is because, if you use the home wire (12-14 gauge) as we all did initially, the adjustment for cell voltage gets REALLY touchy AND the wire will barely be glancing the surface of the water. A hair of evaporation and it disconnects and now you have no clue what PPM you made. With thin copper wire, for 10-12v across the cell (running 10ma at least which is what I do), you'll have maybe 3/4" of the wire submerged where even with evaporation, its unlikely that you won't see it happening where you'll top it off long before the water drops below the end of the wire.
It all seems daunting at first but once you have a setup and you've made it through your first run you'll wonder why you got so hot and bothered about it. Making Colloidal Silver is easy. I can't speak about colloidal gold because I've never made any but the process looks nearly as simple and in some ways simpler.
Do let us know how you made out once you get your first run done and for sure, if you're confused about something, ask questions. Thats what we're all here for.