I got an electronic version of Roark and Young on eBay for $7. Best seven bucks I've ever spent.
It's got great information on stress analysis and what I consider to be indispensible info on plates. I have used the plate formulas in my work, too, so the book paid for itself.
I first came across R&Y in school nearly 20 years ago. It was an expensive book, so I put off buying it (it was often cited in the FEA classes I took). I found a 1940's edition for about $10 just a few years ago. But I snobbishly thought "does this reflect anything Timoshenko did afterwards?" and I convinced myself not to buy that edition. Was I right? Doesn't matter...