I'm wondering on which site / proposal computational geomtry should sit? I'm not sure it has the critical mass to have a site all to it's self but I can see the need for a defined site where computational geomtry questions should sit. I'm thinking about questions like what is the best way to find the radius of a circle given three points on the circumference etc.
There are currently 585 questions tagged geometry on the Math Stack Exchange, and 33 tagged explicitly computational-geometry. You're questions would seem to be welcome there.
We also have cg.computational-geometry on cstheory (and some famous researchers on the topic are highly active users of the site). So if you have a research-level question, come and post it on cstheory. :)