-The first is a bit fussy
-The Second shows good potential. Have you ever done any Graphic design? A tip if not try to keep the colours to a minimum. Always think "Will it Photocopy 100 times and still look good?". Keep working on this one, like I say, it's got potential
-The Third looks like a bit of a rip off of the FR Logo used by Seat. I should know I've just ordered one
Keep in mind what it is you are advertising
Keep reworking them and all of a sudden Voila! You will nail it.
Good luck and keep us posted