Most regular grocery stores carry *some* variety of organics these days. HEB is probably the best bet as one of their top-of-the-line stores has its own organic line and they'll carry that. I have found it to be very hit-or-miss, and just stick to Whole Foods where I *know* I can get at least 95% of what I'm looking for at any given time.
Costco does carry a fair assortment of organics, though, of course, it varies a good bit. Costco is "in town" so for us that's a periodic stop and not a regular one, but even with being pretty super-picky about what we buy, there's a good bit to find there.
There are some co-ops with organic produce around, some centrally located and others in the suburbs, so that can help a lot. There are a couple of organic/grass-fed/natural meat producers that come in on drops every month or two, as well, and some go to the local farmer's markets (most of those are in town, though there's one in Katy, one being planned for Sugar Land, and at least used to be one southwest of Sugar Land).
The cities/counties spray for mosquitoes (nothing you can do about that other than move to the country). It's always at night, so we just ensure no one is outside or going in/out when we hear a truck coming. By morning, there's no odor (and the one day when someone DID have to go out right after a truck, you can't miss the smell - yuck!). There are certainly other natural things you can do to reduce mosquitoes, from special lights to getting a bat colony or banana spiders.
What you do will depend heavily on where you settle. I have found natural bug sprays to be perfectly acceptable (some better than others, of course) for personal protection when we know we're going to be out on a summer evening, but otherwise don't worry too much about it.