In a business situation, I would say the following:
Welcome to XYZ corporation. I am XXX. (if you are speaking to the visitor in person)
Or, if on the telephone: "Hello,XYZ Corporation, XXX speaking."
(You wait for the person to introduce himself or herself. Then, if the person does not offer, ask: "May I ask who you are here to see? May I have your name?" (Or, "may I ask who is calling?" if you're on the telephone) (Usually, people introduce themselves immediately when addressing the reception, so it seems a little odd to ask for someone's name right away. Usually, it might be more polite to wait for the person to identify himself or herself first; then only ask if he or she does not).
It is a pleasure to meet you. (Say this only to a visitor in person; and if you're the receptionist, I don't think I would say "it is a pleasure to meet you," because the visitor is likely here to meet someone else). May I ask who you would like to speak to?
I will let XYZ know that you are here. May I offer you something to drink? Coffee? Tea? Water? (In a business situation, it is preferable not to use "wanna")
One moment please. XYZ will be right with you.