PCV valve can cause a lot of that... an it's $4 and takes less than 2 minutes to replace. Also HIGHLY suspect is MAF sensor needs cleaned, this costs $8 and about 10 minutes of your time with a scew driver.
Vibrations at lower speeds are near drivetrain center. Vibrations at highway-freeway speeds are out at the wheel area.
I could be wrong but this does seem like an easy DIY job. However, as others have said the ignition system isn't really being highlighted. Does it have a check engine light?