sudo configuration for NOPASSWD: ALL

Hey all,

I have a new mac with a fresh 10.8 installed. It's 2 days old and (probably) in the best shape of its life. Here's the problem:

As a Linux guy, I'm using sudo alot and it prompts me for a password every single time. Example:

host_name:~ user_name$ sudo cat /etc/autofs.conf

Password:

etc...

This is getting tedious. In Linux we simply add ourselves to the wheel group and uncomment this line in /etc/sudoers:

# %wheel ALL=(ALL) NOPASSWD: ALL

I've done some troubleshooting on my own but all paths lead to more questions:

Step 1; find out about me:

host_name:~ user_name$ id

uid=501(user_name) gid=20(staff), groups=20(staff), 401(com.apple.access_screensharing), 402(com.apple.sharepoint.group.1), 12(everyone), 33(_appstore), 61(localaccounts), 79(_appserverusr), 80(admin), 81(_appserveradm), 98(_lpadmin), 100(_lpoperator), 204(_developer), 403(com.apple.access_ssh)

-good.

Step 2; grep /etc/passwd for my user account

host_name:~ user_name$ grep user_name /etc/passwd

-nothing.

I can't find my user_name in the password file; OK, now I'm confused.

2 questions - 1 purpose:

1. How do I configure /etc/sudoers to not prompt me for the password at all - ever again? OR
2. What's the preferred method of getting the same functionality in OS X?

Thanks in advance,

TT