This post will be updated regularly and I will be adding more cheats/codes regularly so check back often. Here are some codes I found over the internet.
desk: A08456
kitchen: B54523
jacuzzi: C90761
Please note that these codes are for the Tamagotchi Music Star or V6. To use them go to Tama Town and log in. Then on the right you will see an icon shaped like a guitar pick. Click on that icon and enter the above codes. The items will be added to your inventory. Go to your apartment and you will be able to decorate your room with the items.
A visitor of this site (Kiley) gave us more information about items that are obtained from Tama Town for the Tamagotchi Music star:
"There are only a few specific items that you can give to your Tamagotchi toy, and they are the item's in blocks with the little Tamagotchi icon in the corner of the item's picture.
If the item does not contain the picture, such as most of the furniture and wallpapers, then you will not be able to transfer the item to your Music Star toy.
I tried this myself, and though I haven't bought a lot in TamaTown, the only things that I have been able to send back so far are my instruments.
Only the instruments bought in Music City and the toys can be sent to your Music Star toy. There are only three more items that I know of throughout the Music City that can be given to your toy. There is a CD store where you can sell your CD's and trade them in for items. There are three item's there, the Dream Mic, and the Boy's and Girl's Destiny Star's that you can send back to your Tamagotchi toy. The Mic is an instrument, and the Star's turn your adult boy or girl Tama into one of the secret characters for the Music Star.
The items that you send back to your Tamagotchi Music Star toy, however, and I stress this: only work for your current log in code this means that even if you have the code for an item, and you give it to your friend or the internet, the code won't work for anyone else."