Getting up to speed with 64bit asm

[brethren]

for the last few years i've been programming using x86 asm with linux being my main dev environment. with a new computer on the way i'm looking for resources to do the following

1. get up to speed programming x86-64 as quickly as possible
2. information on porting 32bit linux applications to 64bit

any information, links, evens opinions are welcome

[Rob Neff]

I reference this one heavily:

http://www.x86-64.org/documentation.html

[brethren]

thats perfect exactly what i was looking for