I've been reading this thread on the fly for the past few days and wanted reply again:
Lonesage, keep in mind I wrote my views, as you noted, in 2005. Six and half years ago in China-time is a long time because they've been booming and building like mad --especially in a place like Beijing that was building up for the 2008 Olympics and was no doubt better than when I visited as they were finally getting work off the ground. A place like Tangshan is probably less developed and more like 2005 Beijing, but has no doubt modernized and will have interesting opportunities for you.
Are you being paid a lot? No. But the cost of living in a provincial town (its US sister city is Cedar Rapids, Iowa, though it's still a huge place of over 3m) is going to be lower than Shanghai or Hong Kong, and you can get amazing food for cheap in China if you're willing to try new thing.
As people have mentioned, doing private tutoring is a popular way of getting more income. I know the tutors in Japan do that a lot.
About food and water:
this is the most important health things for you to keep in mind:
(1) Do not, do NOT drink the regular tap water. You will get sick. Bottled water and bottled items are your best bet. This means NO ICE. Also be careful at places that serve fresh produce washed in the water, so stay away from green salads at most places. When I travel to places like that I brush my teeth with bottled water (you'd be surprised how little you really need). You can always rinse your toothbrush after with tap water and then quickly rinse with bottled water. Be careful about swallowing water in the shower. You won't die from any of this, but you will run a big chance of getting painfully sick to your stomach! Don't panic, these rules are actually very easy to follow!
(2) Food. Most Chinese food is pretty well cooked and cheap, which is in your favor. When I was stumbling around Beijing in 2005 I actually found my way into a locals' grocery store (no foreigners, instead people would giggle and say the name foreigner when we walked around), the place was cheap and had plenty of good options. If there's an Asian grocer near you, you can always visit and try and find Chinese items to try now before you go.
(3) With cheap street food the rules-to-live-by are pretty simple: Look for places that people are voting for with their feet--Does the place seem popular? That's a good thing. If people seem to avoid it, that might be a sign that they know something you should know (I learned this one from Andrew Zimmern and it's never steered me wrong). If a place gives you a bad feeling, don't eat there. Again, be sure to watch their hygiene levels to prevent contracting water- or food-borne illnesses.
(4) If you use Tylenol or NyQuil, you can always bring a few large container of pills with you for your trip (don't bring a bunch of small bottles or you might have questions at customs if they search your bag and thing your smuggling narcotics in them).
Don't let your self get paranoid, but always be on the lookout for getting scammed. You will have people try to charge you more than Chinese, even if that happens, often you will think "well, that was still a lot cheaper than in the States". You are going to stick out, so if a person is already a scammer, you're going to be an easy mark. Just don't follow people who invite you to places
unless you know them, they'll often take you someplace where you can be cheated with little recourse. Often they invite you to see things as innocuous as their "art" (its mass-produced), a really good restaurant (where they will charge you 10x what any other place would for the same or worse food--think about that, a good restaurant
won't hide), or a dozen other plays to get you somewhere you shouldn't be. A simple "no thanks", "no" or "boo-yao" will keep you safe. No one is going to abduct you.
Unless you're at a grocery store, department store, American-style store, etc --bargaining is the rule! They will quote you prices a lot higher than what they'd even quote Chinese people, so be prepared to haggle like a pro--or learn how to on the fly
Those are the thoughts off the top of my head, if I can think of more I'll let you know.
When do you leave?
Hope you don't get stuck in
one of these 
LOL!
