Zombies on the loose! What, again! Crud...
Anyway, I would head for the nearby University. Although I would stop at the local K-Mart for a nice 30-06. It can stop most bears, I think it will stop the average zombie.
At the University, I would look for a nice tall building, with a reasonably flat roof. Need a place to grow food. Probably the library.
Books are an amazing resource, for everything from sanitation and medical information, to how to farm, and make or fix things.
Step one, of course, is to clear out the building, step two would be to destroy all the stairwells.
That might sound like a lot of work, but zombies aren't mountain climbers, I think I could get the job down with a good pick, and a couple of hours per stairwell.
And campus buildings all have nice little maps listing all the stairwells.
Now, seeing as I live in a nice modern town, I would gather the components to power my new hideaway. Generators at first, but more to the point, solar and wind powered deices that can be placed around the upper floors of the building.
Not enough power to keep a city going, but enough for my simple needs, and to carry out the plans below.
Easy to imagine a campus library with five, or even six floors. That's a lot of internal water, for starters, though water collection would start on the roof, as well as agriculture. Composting, and human-based fertilizer would also be useful. Waste not, want not. Heck, even urine would be worth collecting, for several uses, especially as a cleaning agent. (Given time to evaporate some, it becomes ammonia.)
As to livestock, small animals, and useful ones, goats, chickens, pigs if I am lucky.
I would avoid shooting at the zombies outside of course, such a ruckus would attract more of them, and there is no end to the number, so I don't expect to end the scourge with a rifle.
The books would help avoid going totally batty. The local campus actual has the equipment to broadcast radio and television. Not sure how useful TV is, but the radio is good.
With luck, and time, I would try and connect as many buildings together across the roof tops. More surface area equals more soil, more sunshine, more wind. This would be after destroying all the first floor stairwells of course. Cautious clensing of the buildings would be required, but I would hope by this time I have lured a few fellow survivors to help with the more laboious tasks.
If we can connect to the dorms, by rope bridge, I imagine, we could have decent living conditions. The cafeteria would probably have some unspoiled food, canned items, beans, rice, the mass quanitites they feed the average student is often made up of such staples. It would also provide the utensils needed to prepare food.
We would spend our spare time building up the stairwell defenses, nto against zombies, but against human mauraders. We would eventually do our best to minimize the number of upwards passages, creating choke points, and kill zones. No sense fooling ourselves into thinking zombies are the only threat, or even the most dangerous one.
Should a break-in occur, or a breakout happen within the area, we would isolate, by cutting bridges, and reclaim as soon as possible. If it is an internal outbreak, that would be fairly easy. If, however, a buildings defenses had overlooked an avenue used by local zombies, that could be more of a task, but I doubt an insurmountable one. Task one would be to find the avenue, and close it proper, to limit the number of internal targets, then lure then to the roof, or to windows, and shoot them.
As we would do our best to make each building self supporting, time would be of little importance.
As the need for a constant defense is quickly eliminated by 'raising our game', so to speak, I feel we could last as long as required, perhaps several generations, but I suspect the powers that be here will find some flaw in my plan.