Engine Hesitation - 2000 Neon

I have a 2000 Neon, 5-spd. I like the car, but recently I've been having trouble with it that is getting worse.

When going through the gears, at lower RPM's, the engine is hesitating badly... to the point where the car lurches. It happens in all gears, even at highway speed. If I'm going 55 in 5th gear, it happens... I down shift to 4th and at the higher RPM, it's fine.

I haven't started diagnosing anything yet, but was wondering if any of you guys/gals have noticed a problem similar to this?

Thanks.... oh yeah, and I'm new here... please be gentle.:cool: