New vs Used Bikes

The first answer is yes, go to a specialist and figure out your size.  It won't matter if you spend a gazillion dollars on a bike if it doesn't fit right.  After that it is all about searching for your bike.  Figure out your budget, use this site to learn about the different components (Most popular are Shimano -105's, Ultegra, or Dura Ace) Don't forget to visit plenty of different shops to see what they have in stock, on-sale, clearance.  It's time consuming but it is worth it.  Keep asking questions on this site because there always seems like there are 5-10 people who are willing to help at all hours of the day or night.  And finally don't forget to post pic's of your new bike right here on BT...just label it "Bike Porn" and we'll all flock to your pic like we do everytime.  Good Luck.

That'd be a definite MAYBE...

The entry-level road bikes at the local shop will be in the $500-700 range.  For this, expect Shimano Sora components, maybe some Tiagra thrown in too.  At the LBS, you would get at least a basic fitting (hopefully) to get the right size frame and have the seatpost/seat adjusted.  (Don't expect a 3-hour fitting and lots of swapping out stems, cranks, etc.)  You also get a tune-up or maybe tune-ups in the first year, as cables relax. 

You can buy these same bikes on Ebay, but they seem to go for $300-400 (plus about $60 shipping).  Now you can take that bike into your LBS and spend another $50 for the fitting (again, a basic fitting, nothing elaborate).  If it needs a tune-up, that can be $30-70 depending on what needs done.  Since you can't try it first, you won't know for sure if the 54 or 56 is the "right" size to start with.  The Ebay seller may or may not have the correct size on the bike and it'd usually be close, but if they list a 56 as a 55, and you think you need a 54-55 (so it should fit), but really need a small 54, you may have a mess.  For this, you won't have a warranty in case something happens with the frame. 

Add it all up, and you may not save as much as you think.  Yes, you can find some used bikes that are worth buying, and I've bought both of my bikes on Ebay (relatively old bikes, so the cost comparison with new isn't anywhere close).  In both cases, the purchase was made with the assumption that I could "throw away" the bike if it didn't work (i.e. I wasn't spending *that* much money).  If you're mechanically inclined, you can get into a "vintage" ride (steel or aluminum frame, downtube shifters) for quite a bit less than a new bike, but this only works if you're competent to repack bearings, adjust shifters, and true wheels yourself.  If you have to pay someone, these bikes will eat you alive.  (You also need to be patient with finding replacement parts, as many of these may have to come from Ebay too.) 

I recommend buying used with some caveats. 

First, spend a few months reading the forums on roadbikereview.com and bikeforums.com, this site and slowtwitch.com.  This will give a foundation of information and help you get an idea of the value of new and used bikes and help you understand the components and values of these components.

Second, get a fitting first so that you know what dimensions will work for you.  I just did this and it cost $75.  You will understand this better once you spend time reading the forums.

Some advantages of buying used

• Someone else takes the initial depreciation
• For a bike that is 1-3 years old, the price will usually be between 40%-70% of the selling price (not the MSRP)
• Often, a used bike will come with accessories that can add up quickly such as pedals, computer, bag, tubes, helmet, etc. 
• If you don't stick with cycling, you will likely be able to sell the bike used for very close to what you paid.  Buy new, and you will loose 30% for sure and likely more.

Disadvantages

• May take a while to find your size in a good deal
• You have know what you are doing and the sizing of many brands
• A fitting will cost you $ where a new, the shop will usually include a fitting
• Depending on you, sometimes walking away when looking at a used item while at there house is more difficult.  It is hard to play business when not in a business....
• Could be hidden issues.  May need an immediate tune up or replacement parts and that could cost and some of the "deal" will be lost.   Again, this is where you need to be informed.

Other recommendations:

Use the watch list on ebay to help identify possible bikes and see what they go for.  I found that getting a really good deal on ebay was usually spoiled by the shipping cost and the nature of bidding.  Additionally, for me, I was just too nervous to pull the trigger on something so expensive without looking at it in person.  Look at your local craigslist.  That is where I found mine just this past weekend and I got a steal and no tax and no shipping. 

I found that in the used market, I still needed to spend $500-$700 to get a good road bike.  It did not seem wise to me to spend $300-400 on a used entry level bike.  The $500-$700 range in the used market, there are alot of bikes that retailed between $900-$1500 roughly.  This could get you a bike that will last a long time and you won't have the desire to immediately upgrade parts or the bike if you really get into it. 

Also, don't forget to have some cash for a helmet, computer, gloves, shorts, bag, spare tubes, tire levers, pump (O2 or hand), etc.  Of course, if you buy used, you might get lucky and get a few of these thrown in. 

Ok that is enough.