"I have your man."
Translation:Ho il vostro uomo.
Because "il" is definite article for masculine singular nouns while "i" is for masculine plural form.
But note that if it there wasn't a possessive (vostro or tuo in this case) the article would be l' (Questo è l'uomo / This is the man)
The definitive article (in this case masculine singular definite article il ) is needed before possesive (vostro/tuo). check this http://italian.about.com/library/fare/blfare132a.htm
Also I presume you wanted to say "Ho io tuo uomo". #1 "io = I" shouldn't be placed behind the verb (It should go before the verb (io ho). #2 the pronoun "io" is not actually necessary since "Ho" the first person singular of the verb "avere" is giving us information who has your man. :)