Hey all, I could use a little bike locking advice from the more experienced commuters. I've been commuting to school and up until now my main form of bike security has been a cheap u-bar and a 40+lb rusty old bike

But I just bought a lighter, nicer bike this weekend. Still nothing fancy or pricey but it looks nice enough to be thief bait so the "how'd you get your bike stolen" thread has me thinking I should reconsider my bike locking options. Could someone advise on what they'd do in my situation?
Situation: I'm on a college campus and my main building is along the main road in town. Lotsa random people going by and there's a pretty high incidence of bike theft.
I'd ideally just take the bike into my office with me, and sometimes I do, especially when I'm working late. But I have two issues with that: 1) They've recently put signs on every door as a reminder that bikes are strictly banned from the building, and 2) there's nothing inside the building to lock my bike to, and I'm in a communal office.
As far as locking it outside, I can lock it to the racks in front of my building (facing the main street) or the back. The front has better lighting and more people around, but it seems to attract more thieves, maybe just because there are more bikes there. There's a bike rack in the back that no one seems to know about- less visible and less lit, but also a lot less traffic.
Which situation seems safer to you all? Risk leaving it unlocked in a communal office (which can be locked, but it open most of the day for other students) or outside? If outside, would you do the area with more visibility or the area that seems to attract less attention?
And as far as bike locks go, what do you all use if you have to lock up outside? Any particular brands that seem to be harder for a thief to defeat? I know any lock mechanism can be defeated but I'd rather invest in one that's as much of a PITA to break as possible, since I need to replace my crappy U-bar anyway.
I think the "how'd you get your bike stolen" thread has me paranoid now that I actually have a bike I like :-/ Thanks for any advice you can give.