I'm not normally a grammar-nazi (I'm half-German and hate that term), as I'm guilty of grammar/spelling mistakes as well. However I have seen this more and more in my travels around the Internet and it bugs the mess out of me. It's kind of like fingernails scratching on a chalk board to me.
"Would of" - This is incorrect.
Used in a sentence - "I would of gone to the Dolphins game, but my car broke down."
It doesn't even make sense.
The proper phrase is:
"would've" which is the abbreviated form of "would have"
Used in a sentence - "I would've gone to the Dolphins game, but my car broke down."
or "I would have gone to the Dolphins game, but my car broke down."
Hopping off of the soap box now. Thank you.