Use plastic beads as spacers? wilco or yorkshire trading sell them cheap in bags.
Various mounts for sale - various dubious designs - some better than others. The smartipi lego camera case so far is the best I tried, nearly perfect. One other case bent the camera pcb so much the camera "eye" popped out. I cut the bend off with a saw.... turned the back into a second case for another camera by drilling a hole for the lens.... Plastic cases are modifiable with pin drills and razor saw.....ideally you need a back to protect the sensitive components. Best would probably be simple front and back with spacers, and lugs sticking out sideways for mounting. Two bits of black lego, drilled for the lens and those (plastic) bolts and bead spacers, would do it. Be very careful fitting it all together, fiddly nuts and bolts and static electricity.... Don't spend too much money!
I use plastic p-clips on carbon fibre rods from model aircraft construction (or disposable chopsticks) with meccano parts to gather it all together to make taller supports. (it will probably fall over so you need a good heavy base)
It all stands on a base made from an old PC heat sink (not many other uses for those apart from letter racks) - looks a bit like an anglepoise lamp or mini crane. You need minimum 30cm cable - the standard cable is stupidly far too short for most uses. Note that the camera faces towards the LAN cable so you need a 180 degree twist or bend on the cable to look out of the window (another reason the standard cable is too * short. I found that a matt black camera shroud, and putting the camera as close to glass window as possible, reduces reflections.
It is better not to mount the camera directly on the main pi-case as you don't want it to move when the LAN cable is nudged, etc.
Also use the p-clips to stop the power cable wobbling - it stops any loss of power issues when curtains get closed, etc.