Newbie Guidance

Welcome!  I'm new to this too but having a lot of fun with it. 

Given your athletic background, the sprint course shouldn't be a problem.  As a warmup event you might want to try the Cedars of Lebanon triathlon in May.  Its a 200 yd pool swim, 10 mile bike and 2 mile run.  That would probably help you get some of the basics squared away. ie. transitions

I think there's a new club in the M'boro/Smyrna area...I think its called Mid tn Multisport.

A cheap road bike will get you started as long as it fits.  Of course, you're going to need a helmet too.

Nutrition...hmm, I'll need to let others chime in on that one.  There's one overall nutrition guideline that I've heard (which makes sense to me) is to shop the perimeter of the grocery store (basically where all the fresh stuff is) versus the interior (where all the processed stuff is).

Congrats on attempting your first triathlon. The Music City Triathlon is a decent beginner triathlon if you aren't cocerned about open water swimming and if you do not mind running the hills in hot weather.

We do have a triathlon club in your area. We actually just started it this year and it has grown to nearly 50 triathletes. You can check us out at www.MidTNMultisport.com or www.Facebook.com/MidTnMultisport. We have members of all skill levels and experience in our club, from beginners to multiple Ironman participants.

Welcome to the triathlon community!  I would also suggest the Old Hickory Lake Triathlon in Hendersonville in June.  It is run by Team Magic (same race director as Music City Triathlon).  They put on a great event.  The Old Hickory race is a little different format due to distance from swim area to the main transition area at the Hendersonville YMCA.  The race is 400y OWS / 1 mile run / 12 mile bike / 2 mile run.  So you have three transitions.  The OWS is in a calm cove in Old Hickory Lake - no current but that may not be a concern for you if you have prior swim experience.  It is also a flatter course than Music City Tri.  Both are good races.

As others have mentioned, there are several local tri clubs and choice may come down to what part of town you live in and where you plan to train.  I am not a member of any but I know there is MidTN Multisport (I think mostly Smyrna/Murfreesboro area), Brentwood Endurance Athletic Team (BEAT), Hendersonville Endurance Athletic Team (HEAT), Nashville Triathlon Club.  There are also several local coaching companies that have "teams" - FTP Coaching, X3 Endurance.  Most of these can be found on Facebook.  I live in Mt Juliet and do most my training in that area and mostly in the early morning hours to limit time away from family.  Would like to do more group training but not an option for me right now.

I did the Music City Sprint last summer as my first triathlon, and I thought it was great! I was a little bit leary of getting into the Cumberland River, but once in everything was fine. 

Also: I didn't own a bike when I signed up for last year's tri, and I signed up in June.  I went with a new but VERY cheap road bike (literally the cheapest one I could find online, pretty sure it was less than $200), and even though I have some serious bike envy at each event I go to, it gets me through just fine.

Good luck!

Run - As for the run course, I participated in the Color Run (a fun run, I know) which has pretty much the same path, minus a few turns, so I'm confident I'll be ok with the run. My biggest obstacle has been a battle with poreneal tendonitis. I think I've finally tamed it with some different insoles and KT Tape.

Bike - I actually just talked my mom into giving me her bike. It is fairly new and just sitting in her garage collecting dust. I have no idea what type of bike (mountain, I'm sure) or what condition it is in but maybe with a little luck and love it'll do for a while.

Swim - All of my swim experience has been in a pool. I do intend on getting some OWS time in once it warms up.

I think I'll try the Cedars of Lebanon Tri. I'm confident I can get to where I need to be by then. If that goes well, and I can get some OWS time in, I'll definitely look into the Old Hickory Lake Tri.

I did notice that Team-Magic requires a USAT membership. Would I be better off just buying the year membership for $45 versus the 1-day for $12? I didn't know how many, or if any, other tri's required this.

All USAT sanctioned races will require the membership.  So it really comes down to a cost-benefit for you.  If you do at least 3 races then you are pretty close to breaking even (as opposed to paying the one-day licenses each time).  Most of have the USAT membership and get our use out of it. 

Good luck with your training.  Feel free to ask all the questions you want on this board...someone will have the answer (or point you in the right direction)