Road Bike Question please?

I'm guessing you mean $500. Questions on this website come from every English speaking country in the world. Be specific.

Road bikes start around $650 to $700. Stay away from the cheap crap in discount stores & most of them through Amazon.com. You find out what frame size you need by going to a bike shop. That's why they have salespeople. That's why test riding a bike is free.

For example, you can buy this Diamondback Podium 1 on Amazon for $605. http://www.amazon.com/Diamondback-Podium-Wheels-Silver-Large/dp/B008O0XTUG/ref=sr_1_5?s=cycling&ie=UTF8&qid=1373786218&sr=1-5 But you'll still need to assemble & tune it up yourself. But then, since you assembled it, it has no warranty. That's right. Diamondback will not honor any warranty unless the bike is professionally assembled & tuned up at a Diamondback or Raleigh dealer.

You always want to look for an 8 speed cassette, double wall rims and Shimano STI shifter/brake lever combo or comparable shifters from MicroShift or SRAM. If you can't both shift gears & brake from the same hand position, avoid it.

I don't think you could get a reliable and decent Road Bike with $500.A good Entry-Level Road Bike stars around the $750-800 mark...or even close to a grand.And since you're new,don't every buy from the Internet as you're too inexperienced to know what you're getting yet...sorry to say this.Its best to buy a Road Bike from a Local Bike Shop as its there,you could go through Bike fitting,important when buying a Road Bike,and buy the correct Bike for you.