Happy shopping,
I can only relate my experience. The good news is the $1000 will get you near the heavy duty treadmills (hope for a sale). When I was looking a few years ago I was becoming frustrated as the good ones (close to health club quality) were all over $1500 or so. That is not to say you can't get a decent one for under $1,000. It's just my wife and I were both using our old one almost every day so we needed a pretty sturdy one.
We wanted a larger running surface than the discount ones offered. Also wanted a comfortable running rack with a little spring. We didn't need all the bells let alone the whistles. We wanted solid more than fancy.
I ended up at Sear of all places. They had a NordicTrack that had been returned. The new one was $1,500 and they were selling this one for $750. Nothing wrong with it, just returned. Well to be sure I purchased the 3 year warranty for around $200. It has been going for almost 5 years now. I've had to replace a bolt or two but that's it.
Most treadmill company price their treadmills into categories. Like home, gym, professional, etc. Within each category they have different models that have a variety of features but the basic treadmill is the same. Just like buying a car. Say you buy a Chevy Caviler. There are many different trim packages for a Caviler but you still get the same basic package underneath. You have to step up to the next category to get something with a different base, bigger motor, larger tires, etc. In treadmills the next step would be a larger motor, large running surface, etc. My suggestion is to buy the lowest model in the highest category you can. Like instead of a top of the line Caviler with leather seats you buy a stripped down Malibu (or whatever the next model is). Hope this makes sense.
So I'd say do your homework. Decide what is important to you. Large running track, bells and whistles, ability to fold up and move, etc. Then go shopping. Just start asking questions. Go to a local health equipment store, go to Sports Authority, Sears, and just ask all sorts of questions. Make sure you wear you running shoes so you can try them all. Might even want to look in the newspaper. Even though you won't get a warranty, there are a lot of people out there with money (nice treadmill) and no motivation (selling it).
Good luck and have fun shopping!
Duane