How Can I Ensure I can Access Steam w/out Internet

Keep your Steam updated? However, it still requires you to log in every now and then to check for updates.

Also, go DRM-free maybe?

Log in, fire offline mode once you're online, fire up offline mode whenever.

Magic.

Seriously tho. That's how it works. You gotta go in offline mode at least once while you're online or it won't work properly due to some things they check. You might have to do that occasionally as well. How often, don't ask me.

Supposedly if you keep a copy of a file called ClientRegistry.blob (haha funniest file extension name ever?) when you lose online access to steam for too long you just copy over the newer Clientregistry file (steam creates a new one when you log in and overwrting the old one) then change the PC clock's time to before the date of the old back up file...you can regain and keep access for a time...dunno haven't had to try it yet and may not be a viable method anymore after updates or who knows :/

This was the worst. My friends and I would all get together to plan LAN games, and someone would have to connect to the internet to log into steam in Offline Mode. Then we'd get that sorted and they'd need to connect to contact a key server. It was terrible.