Fuel filter?

Lately my 2000 Cavalier has been getting lower gas mileage and I've noticed it having less power. Is this probably the fuel filter?

a clogged fuel filter will usually result in your car sputtering and possibly stalling, it will also have very poor acceleration as the engine is starved for gas

I would recommend a tuneup. Try changing the following things:

Spark Plugs
Spark Plug wires (if damaged)
Oil and Filter
O2 Sensor

That should probably help some. The biggest culprit out of the listed is probably the O2 sensor, good luck

don't forget the air filter!

I just replaced the air filter a couple thousand miles ago.

Today I started my car, but it didn't start right away. These things make it sound like its most likely that my fuel filter needs replaced?

I also looked at the filter today, the connection on the rear end was kind of rusted, not sure if its something I could do myself.

Any thoughts?