Locks are just to keep shady people honest. It won't deter serious thieves. It might deter opportunists.

My solution is to use only a $100 hybrid bike for situations where I'd need to lock it up. I use a fairly heavy duty cable and one of those round storage unit locks that minimizes any exposed shank. That's my grocery getter and errand bike. It's what I take for casual rides around town where I might need to lock it up out of sight.

And I try to pick areas where thieves wouldn't want to be seen. Texans tend to intervene more when they see something shady going on, so unless it's a really bad part of a big city like Houston or Dallas, chances are thieves won't take a chance on whipping out the bolt cutters on a bike locked in front of a busy grocery store.

If it gets stolen, I'd just check craigslist and find another similar hybrid or 1980s-'90s era mountain bike. There are a zillion of 'em, all good bikes but inexpensive.

Regarding tracking devices, yup, they're becoming cost effective enough that soon we'll be able to afford 'em for our own bikes. Most rental bikes -- city and privately owned -- have GPS trackers now. It's integrated into the entire rental system. And those are pretty heavy bikes that few people would bother stealing anyway.