vocal monitors?, ...what are those


do you mean nearfield monitors maybe?...
there are so manny different brands and thus promises that you would need a chainsaw to cut all the trees to be able to see something if you know what i mean, ...how big do you want them, what is your budget?
go to a big music store where they sell most of the brands like KRK, tannoy, genelec etc, bring some reference material like your favourite cd of wich you know how it sounds and have fun

, ....myselve is a fan of 15" sofit mounted tannoy monitors, nice and big