Comprehensive compilation of conic section formulae
Solution 1:
Appendix 1 of Keith Kendig's Conics seems to carry a lot of the formulae I want. On the other hand, I'd sure be interested in an even more extensive listing...
Solution 2:
An old rich treatise is
- John Casey: A treatise on the analytical geometry of the point, line, circle, and conic sections. Second edition 1893. Hodges, Figgis, & Co. (Ltd.) Dublin; Longmans, Green & Co. London; Dublin University Press.
That one also contains background for the complex tangent-through-focus topic which I find so useful in determining foci.