I purchased a laptop style power adapter for my rostock-mini from 321-short-circuit on ebay. It came with a power inlet jack. I made a block that holds the power inlet and the power switch and is bolted to the bottom platform of my rostock-mini.
I have a matching bottom block for my wiring guides here: http://www.thingiverse.com/thing:65792
Print it. Drill out the 3mm mounting holes with a 3mm or 1/8" drill bit. Use 2.5mm screws (10mm long) to mount the power jack into the block (my switch snapped in).
If you want a side by side configuration, or only want one of the two, or if your switch is of a different size from mine, edit the SCAD file and re-generate the STL file.