Q)I really want to see DVD box set. It has the concerts and two extra episodes on. Where can I get them? And what about dolls and game?
A)I know some Japanese online shops which deal with international orders (Japanese only). If you don't read Japanese, some sort of  web translator might help you.  Amikai, for instance.
Amazon.co.jp / DVDbox.1-4,Video, CD

keyword ”ウェディングピーチ”
Honyasan.com/ DVD box2 and some videos are available.
Kinokuniya bookweb / Only DVD box 4 is available.(small stock) About international orders is here.

About dolls and games, all of them are out of stock, unfortunately. The place where you might be able to get them is Auctions in Japan, I guess. There are Japanese fans who got WP goods in there.
Q) It's possible to have a complete list of all the toys and dolls related to WP and Momoko?
A)  I'm afraid it is impossible.  We don't have a such list, besides, I, myself didn't know them completely because there are so many products. But I'll add some goods to Momoyome's goods section, so you'll be able to see some of them in there.