We started our kids on this last year and they loved it! Most of the shops carry at least some pins and there is a huge pin shop at Downtown Disney. We bought them a start up lanyard that they wear around their neck, at one of the stands. The start up packs usually come with a lanyard (there are different ones like Mickey, Tinkerbell, etc.) and four pins, two to keep and two identicals to trade away.
My kids love to trade with cast members. The managers at the hotels always have great pins it seems and are more than willing to stop what they are doing to trade with a child. Cast members who are wearing a green lanyard will only trade with a child, black lanyards will trade with adults and kids.
You can also ocassionally try
www.disneydirect.com to see if they have another sale on pins. (they just ended on on May 31, I think). Have fun, but be careful....it's addictiing!!!
