I think any of the long-term brands are good. The all metal construction will last you close to forever. So brands like Singer, Janome, Viking, Pfaff, Bernina. If you go visiting the local sewing shops for traded in machines, be prepared to be shown the newst models as well.

They are after all, sales people. I always like to call first. Tell them what your price range is and what you're looking for. They can probably give you a good idea of whether or not they can meet your needs. Then when you go in, ask for the same person you spoke with on the phone.
Have you asked around in your family? Maybe someone has an old machine they "haven't used in years!" that you could use...