There are only 3 argonians you can marry that I know of. Of course two are male the other female. The male argonian is a fisherman near Darkwater crossing, once you rescue him (and find him) he'll be receptive to the marriage. The other male is in Windhelm,
he runs the Argonian Assemblage. If you complete a favor for him he will become friendly. The only female argonian is also in Windhelm at the Assemblage, but sometimes at the docks as well. Complete a favor for her and she will be receptive as well.