Frankly I can't see that as being wise... never heard of it, in fact.
A Wedding is just like a Corporate gig; you are paid a flat rate. You do not solicit tips or pass out your own card (if the event organizer brought you in, you are their "property" -- it's a professional courtesy)
I know it's quite the common practice but you will find that the upper-end pros NEVER stoop to such antics. They take their fee, which is typically in the $800.00 and up range (several of my friends in the Manhattan area see $1,500.00 to about $2,000.00 regularly for this kind of date).
I really believe you might want to re-evaluate things a bit; especially how you want the paying public to view you.
