I have a UK, (PAL) Xbox. I have heard that there has been a chip developed that would enable me to play US-coded games.
I know that this isn’t recommended by Microsoft, and will invalidate my warranty, however is it still legal? If not please don’t answer the next question.
If so, does anybody know where i can get one?
theres certainly ones out there for the PS http://forums.psxforum.com/showthread.php?threadid=2047 , but I haven’t heard anything for the Xbox
There are Mod Chips for just about everything out there. Here is one place you can get an XBox modchip for about $90 USD.
Modchips
Good luck getting it on the XBox. I wouldn’t suggest it if you have shaky hands. 
LilShieste