How to obtain the result of a chemical reaction given two components?

Yes, Google.

If somebody's put the result of the reaction on the net, google will know about it. Doing the reactions of any two elements accurately and definitively would basically require somebody to program a universe simulator, wheras we already have a perfectly good universe to test things out manually, right here.

edit: CW so people can downvote me, this answer really isn't deserving of a bounty, on the offchance to OP doesn't return in time.

Would this Chemical Equations Calculator do? If not, there is a lot of hits returned for the search "chemical reaction calculator online".

Computational Chemistry -- that is, simulating the chemical reactions rather than simply having a database of reactants -- is well known as one of the classic supercomputer CPU sinks. Wikipedia has an introduction, and Google will give the expected large number of links.