Update 06/25/11 : As of today, there are still Birthday Packs availale from NCSX.
If you never got a hold of this awesome Sonic Adventure 2 Collector’s edition then now is your chance. NCSX still has unsealed copies from the original release (6/23/01), set at $63.90. Their goal is to sell them all by June 23, 2011 (Sonic’s 20th Anniversary).
I just ordered my second one ( I got my first one back in 03). If I were you I’d order it now because they’ll be gone pretty soon. It seems their stock is now less than 30 !!!
Here is the link to the product page;