First off, avoid two bars--Holocene and Tube--at all costs. Everyone there has the body fat of an anorexic child on the Atkins diet, so you won't get any good eatin' on those bones. Grr! Plus, the brains of all those kids are completely pickled with gin... Which, in my humble zombie opinion, completely ruins the taste and texture of the most delectable human organ.
Instead, hang outside Mandarin House Restaurant--on SW Ankeny between 1st and 2nd Avenues--on Fridays from 5 pm to 7 pm... because this is when and where the Oregon Mensa crowd hangs out! Yaargh! It's like a smorgasbord of oversized, overripe brains, and these smarties usually drink red wine--which gives the brain a rich, oaky flavor. For other delectable brains, loiter around outside Powell's Books on SW 11th and Burnside. Tons of tea-drinking brainiacs frequent this block daily... and with all the hobo teens around, no one will even notice you!
But if you have a sweet tooth, I recommend the Lloyd Center Food Court. (Don't worry about being seen, either--most people will just think you're a Hot Topic employee on break.) I've never seen so much good noshing in one place in my entire afterlife! Just yesterday, I was stripping the fat off of a chubby tween near the Chicken Connection, when a gang of bubble butts came truckin' out of the theater after seeing Princess Diaries 2. Pumped full of Dots and Coca-Cola, their brains were like candied hams! I had to stuff that tween I was working on into a dumpster for later dining, just so I could herd up the kids from the theater for a little sweet treat. In short, the mall is like flea season at a dog ranch--and it's on the MAX line, so it's a breeze to get there!
In summation, have a good time and be creative! I mean, if you're gonna be undead forever you might as well enjoy yourself, right? Don't wallow in the inherent hopelessness of your situation--that's for vampires. Instead, find your zombie Zen, give into your bloodlust, work on developing a menacing shamble, and just go with it. Yarrrgh! Rrrgh!