Now, the bad news. I'm having a lot more trouble this year with bugs and disease than I expected, based on my experience with a community garden plot last year. Some of the problems I've diagnosed already, others I'm stumped. Any help would be appreciated!
First, the tomatoes:
I'm having trouble with two viral infections right now. Curly Top and Fusarium Wilt. They're mostly affecting the non-resistant varieties, but even some hybrids are suffering.
This plant has Tomato Hornback caterpillar damage and Curly Top:
Here's a close up of Curly Top damage. The plants are stunted and not flowering. 
The only solution for these infections is removal of the plant. Ugh. It's almost half of my 20 plants! Some of the heirlooms are also showing signs of Fusarium Wilt, which, according to my references, may require soil solarization to prevent this from happening next year too. It will be a much smaller tomato yield than I hoped for this year, although I suppose with my late start and early growth issues, can't be a total surprise.
My trellised cantaloupes having symptoms of powdery mildew. I treated that this morning with a mixture of baking soda and dish soap dissolved in water. My references say that it's a good organic fungicide and fungal preventative. Hopefully it works! Those cantaloupes are looking wonderful.
Some of my peppers are having something like blossom-end rot on them, although my references describe it as "water soaked, sunken areas." Although the fruit tips are brown, shrunken, and, and sunken, they don't seem "water-soaked." Does this look like typical blossom end rot? It's spread across multiple varieties, all over the garden. 
My green bell pepper has an odd spot on it. It's dry and paper thin where you see the white in this picture. Any ideas? 
And last major issue: What the heck are these bugs? They're exclusively on my eggplants. They look way too big to be aphids, and they seem to have two forms, the green stem huggers, and then these black and green shell-like leaf-dwellers. They like to congregate in the crevices between blossoms and the blossom clusters wilt and fall off.





Responses
So between burning myself out on tomatoes (just growing too many) and having trouble keeping them healthy for the entire growing season...I decided to take a new approach this year. All but two of my plants are volunteers...and they are doing really well so far! At this point its hard to say if its relevant to them being volunteers or if I'm just doing something right this year.
I don't know much about "volunteer gardening" (if thats even a real term) but it seemed like a natural approach to me.
As for the eggplant the flea beetle is the most common pest, but those green winged things are definitely not them. I've already looked through a variety of sources for answer but haven't had any luck, but if I figure it out I will let you know!
Oh and thanks for mentioning the powdery mildew recipe! I think I'm going to try that.
Claire - is the powdery mildew on your cantaloupes resulting in the brown leaves you show? Both my cantaloupe and watermelon have withered up - brown leaves - brown stems. The fruits are still there and attached, but don't really seem to be growing much anymore... :(