Making an offer process?

[Sean Gallagher]

I suppose there is a little more to this then simply running around and throwing numbers out there to listing agents.  Does an offer have to be submitted in legal binding contract form so that the seller could sign if accepting the offer?  

For instance say I don't have time to check out a property and from what I have see so far from pictures etc I want to get an offer out there to get my foot in the door, knowing my bottom price to test the waters before I have a shot to go actually view the property.

I assume I have to work through my agent to make the offers for me? Speaking properties on the MLS.