OK, we know Apple's Maps app in iOS 6 hasn't been a favorite feature for many people (allow me a bit of sarcasm). Yes, it adds realtime voice navigation, keeps walking directions and links to transit apps -- but it's still painful in many spots.
You still, however, must travel from point A to point B without the Google Maps app you used to know. All is not lost if you are resourceful, and we know our readers are.
Of course, you can put Google Maps back on your iPhone as a web app, or do the same with Nokia's excellent NAVTEQ-powered maps. Just bring up Safari and type maps.google.com, then save the page to your home screen via the action button. It's not as pretty as Apple Maps, but it has the benefit of Google's years of experience and data.
When you first bring Google Maps up, you'll be asked if you want to save Google Maps as on icon on the desktop, and that might be a good idea. Of course, you won't be using Siri to choose destinations by voice, and you won't get spoken turn-by-turn directions, but you'll get transit directions, and even bicycle routes. (The webpage should prompt you to let it access the phone's location.)
Google's iOS search app and the Google Places/Google+ Local app all connect to the web-based Google Maps as well. If you're searching for local resources and Maps's database doesn't have what you need (a common reported issue), you can try one of these instead.
What else works? On the pay side of the ledger, Navigon has just upgraded its family of apps with transit directions and integration with Apple Maps. It also features Google Street View and local search, and spoken turn-by-turn directions.
Other mapping apps are currently on sale, like the Western States (US $24.99 for their regional version). Motion X GPS Drive starts at $0.99 with several options available as in-app purchases. TeleNav GPS Plus is another nice app for $0.99, but you'll need a subscription to use it beyond 30 days. Garmin, which owns Navigon, will have an update to StreetPilot USA any day now with Google Street View and public transit directions. If all you're missing is Street View, check out the $0.99 Live Street View app.
There are free apps of course, including the MapQuest app from our corporate cousin (both TUAW and MapQuest are owned by AOL) and the popular-with-commenters Waze. Many of the free nav apps depend on the same data that Apple Maps users are complaining about, so that's probably not a sensible way to go.
One bright spot in this rather dismal situation is that I foresee prices of paid apps dropping. The Apple Maps solution is working fine for many users here in the US. It's not holding up so well overseas, and even the US version has plenty of holes. But free is hard to compete with and I expect Apple to step its game up, since a reputation is a horrible thing to waste, and the paid apps will likely get cheaper even if those solutions are better in many ways.
We're open to some suggestions, so let us know in comments if you have some good substitutes.