Triathletes: I Need Bike Advice!

  This post is going out to all my amazing triathlete readers.  I need help!!  I want to start training learning to ride a road bike as soon as possible, like yesterday.  Only problem is my current bike looks like this:

     Not very conducive to racing, I would think.  So I've started looking into purchasing a road bike, my birthday is in a week-ish and I have already talked to Matt about considering it my birthday present.  It doesn't matter if how we split the cost, it is all "our money."  

     I have looked at some bikes online, but I don't know what I am looking for, how cheap I can go and still get decent quality, if there are sites that have cheaper prices/ used bikes.   Yesterday I stopped in a local bike store so that I could talk to someone who knows about bikes in person.  The older gentleman that I talked to pretty much tried to sell me a brand new 2011 $1,000+ road bike.  The bike was beautiful, but I am not ready to drop a grand for my first sprint triathlon.  The other option he had for me was another brand new-not even out of the box yet $800 road bike which "had the same quality as the more expensive bikes."  Still a little steep for my first bike.  

      I decided to stop in Sport's Authority and see what they had as far as road bikes.  They had one women's bike for $450, I just tried to find it online right but I don't see it.  They do however have this one online for $209!

Is this doable for getting started?  I still plan to be competitive and go for time, as opposed to just completing it.  

I also found this site: BikesDirect.com, which seems to have some nice bikes for discount prices.

For example this bike:

Originally $1595, Now $600

Questions for all you experienced tri-ers out there:

What are the best sites for good bike deals?

What should I be looking for in a bike?

How will it effect me if I go for a cheaper bike?

Best brands?

What other bike equipment do I need?

Anything else I need to know?

Help! Please :D

Note: The tri that I have scheduled to be my first is at the very end of August, but I have been contemplating strongly leaning towards entering one in June/July in order to gain some experience.   I really want to kick ass in the August one and I doubt things will go smoothly without any prior tri experience.