Clueless newbie needs a road/tri bike

Check out craigslist. You can usually find some good deals on there.

Also, make sure you get a fit so you know that the bike will fit you.

You are in exactly the same spot that I was in 6 months ago (except I didn't even have the mountain bike as a backup).  I did the Craigslist thing, but in the end I didn't feel like I knew enough to make a confident purchase there (also, the number of road bikes vs. mountain or BMX bikes for sale there was miniscule and made searching very tedious).  So I bit the bullet and went to a few LBS around me, before finally deciding which shop I liked best and working with them to get what I wanted.  In the end, I came away with a perfectly acceptable entry-level road bike that, after a discount from being in my local TRI club (thank you!!!), came down to a price of just over the $700 you have saved up (I think after tax, and including a new helmet, two water bottle cages, and a very basic computer I came in at $890).

Keep at it, and make sure that if you do go to the LBS that you are just very clear on your requirements for the bike, both performance-wise and price-wise.  If that isn't the route you take, then what I would do is go to the LBS anyway and they will at least get you onto the correct framesize, which you can then use to filter your Craigslist searching a bit.

Sun & Ski has some great discounts on bike from the 2011 and 2010 season.

I picked up a Marin Cyclocross bike with an 899MSRP for 399.

But you should know the frame size.

IMO for a Newbie getting fit is not that important.

Becasue evrything will feel weird and uncommfy.

You need to get on a roadbike ride it and then adjsut thigns here and there.

But I hear you, I had a MTB and hated riding it on the streets, I would be dying doing 12mph!

Props to the tough people that do triathlons on mtn bikes!

Well, here's the problem when a newb wants to buy a road bike:  As a newb, you don't know how to evaluate a potential bike's value and suitability.  In my opinion there are 2 things you can do:

1) Find an experienced cyclist (or triathlete) to help you shop, including looking at potential used bikes with you.

2) Buy from a bike shop (and some of them carry used bikes).

To further complicate the situation, I don't think that $700 will get you a sufficient road bike of the new variety.  So assuming you don't want to use credit to supplement your purchase, you will have to either save until it's doubled or shop for used bikes.

And definitely get a road bike, not a tri bike at this point!

you might want to check out bikesdirect.com as well.

The financially conservative side of me absolutely cringes at the idea of someone financing a bike purchase.  But I digress.

I bought a road bike (Trek Madone 4.5 if memory serves - all carbon, 105 components) and it rides like a dream compared the heavy mountain/hybrid style bikes I've owned or ridden in the past.  I am a newbie and looked at bikesdirect.com, but I really wanted a good fit.  I ended up getting a 2011 close-out in January for just shy of $1700 (a good deal I believe for that specific bike).

I just completed my first HIM, and I cannot imagine doing it on a mountain bike.  Perhaps look at some used bikes at local bike shops to keep the cost manageable.  But I would caution you against throwing that $700 at the first new bike you can afford.  It is likely to have lousy components that will bug the heck out of you on longer races and training rides.  Just my opinion, and I'm no bike snob.  I was floored at how expensive road bikes can be.

I think you do need a few more hundred $$, but if you can get to the 1k-$1,200 range, you should be able to walk into a bike shop and walk out with a bike that fits well, rides perfectly fine and will last essentially however long you want it to if you keep up with the maintenance.

The risk of buying used is you won't have any idea if the bike fits you well or not.  At a bike shop, you'll at least get the expertise of the guy selling the bike...and he'll put you on a trainer and adjust some things and make sure it's relatively comfortable before you walk out.  These guys get dogged on this site quite a bit because most are not hard core fitters with certifications and everything, but it's way better than nothing.  And if the first couple rides don't feel good, you can go back in and they'll help you.

Read reviews and ask around for a good bike shop, or even better, a good bike shop owner/salesperson that is known in the area to know what he's doing.  Go meet with him now - even with only your $700 - and just pick his brain.  Be honest about your goals and how much money you have and he'll shoot straight with you.

Walmart?  Im in my third year on a $150 walmart road bike and I still use it and like it.  Its still heavy but you are in the right position and have skinnier tires.

Also maybe you will get some better craigslist/ebay deals in Winter/Spring.  More people will be looking in their garage and see a bike they havent used in a long time and want to get rid of it, in the summer the mentality might be more "eh I might use that".

Autumn/winter will also be a better time to pick up discounted bikes at a LBS.  They will be trying to get rid of last years models to make room for next year and also trying to boost sales in a typically slow part of the year.

If you have a decent LBS in your area, head on over.

You can likely get a decent entry level roadbike for $700. 

Thanks everyone.  I really appreciate the feedback.

I headed over to an LBS and as most of you predicted looks like I need my piggy bank. I ended up with a 15 year old kid as my salesperson -- not encouraging -- but the gray haired dude seemed a bit more knowledgeable (but was helping other people)

Low end is 650-900, carbon forks seem to come into the picture around the 1000 mark.  There is another thread on the forum with a guy looking for a bike for his wife - similar situation.  I'll keep my eye on that thread too.

I just picked-up a Specialized Allez (base model with low-end components) for $739, and it has a carbon fork.  I wanted to upgrade to either the sport or elite model, but chose to put some money into pedals, shoes, and a computer instead.  I've put about 60 miles on it so far and couldn't be happier (except for the TB ).

I realize I may be opening a can of worms on the mail order thing, but I know if people who ordered at bieksdirect and are happy.  Check this out:

http://www.bikesdirect.com/products/dawes/lt1500.htm

Carbon fork, clip on aerobars, and it's new. Something to think about.

ANY road bike that fits you will be a lot better than your mountain bike for triathlons.

Save for a few more months and start looking out for close out sales.  The 2013 bikes will be coming in a few months, and I bet the 2011 or 2010 that's still around the LBS will be going for better deals.  If you have a local cycling club in the area, try to connect with them.  Most of the cycling club members would love to help out a newbie - sometimes, some of them may even have a spare bike or two that they really wouldn't mind selling.  Worst case, you may be able to find someone that can help you look at used bikes.

You can find a lot of decent used choices at $700-800.  Probably some aluminum frame bike that's  3-5 yrs old but will likely have a carbon fork and perhaps Shimano 105  or therebouts components...but you have to have someone knowledgeable help you with the purchase.  This is especially true if you ride an 'average' size bike (the extremes, either small or very large are harder to come by used).  If you buy used though, save some money for some rehab (depending on what you buy - bar tape, perhaps some maintenance parts, a spares kit (tube, CO2 cartridge at minimum), as well as equipment if you need them (I presume you already have a helmet).