If it's your 1st F&W Fest and you're in a time crunch, the guides may be useful. I don't think there's any info that can't be pulled from various websites and boards for free, but you may need to pour through a lot of posts and info. There's a good ongoing F&W thread in the DIS restaurant board pinned at the top. But, the Disney Food Blog has been covering the F&W for years and done a great job distilling all the info down into the guide.
Personally I got all the info I needed to know from reading the DIS threads, DFB, and easywdw stuff for free.