Wes, I've done a fair amount of canning over the years (both water-bath and pressure canning), and I agree with GoatDriver that the Ball canning book is an excellent reference, although my personal favorite is "Putting Food By"
https://www.amazon.com/dp/B0053YNF46/
Anything acidic is easy to can because the risk of spoilage is much lower. Things like low-acid vegetables (such as beets, carrots, beans) need to be pressure canned to be safe. I believe the problem with canning homemade spaghetti sauce applies to sauce that contains meat, which has a high risk of spoilage. There are a lot of recipes "out there" that use pretty questionable methods of canning, and improperly canned food can contain some pretty nasty organisms -- so, although you could certainly find many people that would disagree with me on this point, I would much rather err on the side of safety and decrease the chance of someone becoming ill from food that I canned.