I use an ADF (Score 1)

I've had some success doing exactly this. I prepared the magazines by cutting the spines off w/ a special paper cutter. It pinches down on the magazine and slides across the sheets cutter deeper each time. Next, i put the sheets in an Automatic Document Feeder scanner. We have some nice duplex ones, but i use a cheaper, single sided scanner w/ luck. i use Adobe Acrobat 8.1 to scan and save as a PDF. Acrobat OCRs the text and it is searchable using DTsearch, but Google Desktop or MS Desktop search would work too.

There are a couple things that can cause you trouble. The paper must not be too wide or it will get jammed. If the spine isn't cut smoothly, it will also jam. Sometimes it just jams for no reason. And sometimes when it jams, it ruins the sheet. Even though all of this, i've scanned about 60 magazines and use them to search through. Hope that helps!