We are going to use a company called Fun Services. We used them for our Christmas shop and it was extremely organized. We have had redemption centers in the past and we purchased items from wholesale vendors but you will spend alot of money and the hard thing wil be knowing how much of each item and what age group will want that particular item. When using the professional groups they bring everything and you only pay for what you use. This saves alot of money and you won't be stuck with all of the items that the kids didn't want. In our case space is a huge factor every year in that we have none and where can we store the leftovers each year? Try using a company like Fun Services. You won't be sorry.
I'm going to bump this up one more time....if you have any suggestions on this topic I'd love to hear them. Also - even if you haven't done this yourself...what type of selection / amount of items do you think we'd need to have on hand?