Do forum or website exist where can buy things not usually sold with bitcoin?
The Marketplace on BitcoinTalk can be used.  Simply prefix your post's title with "[WTB]" which means "Want To Buy".

Discussion:


http://bitcointalk.org/index.php?topic=64607.0


Marketplace board:


http://bitcointalk.org/index.php?board=5.0


Also, the Bitcoin-otc marketplace can be used to place requests, if you are looking to buy.


http://bitcoin-otc.com/vieworderbook.php