When I decided to get a road bike, I did my homework.
I asked a lot of different cyclists their opinions about makes, frames, material, gearing etc. I also found helpful information at this site: http://thebikepalace.com/page.cfm?PageID=52

When I started actively looking, I had already decided on:
• My ballpark size - I had my inseam measured
• Max. price for a starter bike: $1500
• Looking for last year's model to get a better deal
• The min. components I would settle for: 105s or Campy Veloces
• Carbon forks and a triple ring

Once I knew this, I pulled up as many bike specs as I could from the web, narrowed it down to 6-7 bikes. I then took these printouts around to experienced cyclists and asked for the pros and cons of each. Down to 4 choices.

After that, it was just a matter of calling or visiting bike shops (13 in all) to see if they had any of these bikes in my size to test out. Some bikes were prefectly fine, but as soon as I sat on them I wasn't happy. The last bike I got on, I sat on it and everything just seemed to fit perfectly. I have no explanation as to why I like it, I just did.
To make room for next year's bikes, the LBS knocked my price down from $1300 to $1000 so I have been able to put in $500 more in upgrades (carbon handlebars, etc.) All in all, a happy shopping trip!