Which components, exactly? :) I buy most one-off parts-n-pieces through DigiKey. I've done a ton of prototype PCB's with ExpressPCB. (expresspcb.com) For CN

Which components, exactly? :) I buy most one-off parts-n-pieces through DigiKey. I've done a ton of prototype PCB's with ExpressPCB. (expresspcb.com) For CNC work, vacuum-form molds, and injection mold ME's, I keep some local folks on speed-dial. I often reduce costs here by doing the roughing-in of mechanicals myself. I have a moderately well enough equipped shop that I can do prototypes for cases, bezels, etc. myself. I will most often sketch something out freehand (I'm a HORRIBLE artist though), then make a wood model to see what it looks like "in person". Then (generally) do a fiberglass model (because it's cheap and easy to work with) of the part, check rough fitment, THEN go to an ME or CNC person to discuss costs and production times. I've done that cycle enough times now that I generally know how to make something "manufacturable". IE: little things, like complex curves for an injection molded part, can add a comma or two to the mold costs :) In any case, having a physical part to base your discussions off of makes things easier. Most of the stuff I've done hasn't warranted a bona-fide Industrial Design cycle (or if it was warranted, it wasn't budgeted :) )