It's a lot to deal with, isn't it? You sign up for a race, you start running around the block, attending bike classes at your local gym, struggling across the local pool in 25- and 50-yard bursts . . . And you're getting the hang of it. You're starting to feel really good about finishing that first race. You're pretty sure that you can do it.
But you're also trolling around the internet like a madman. Madwoman. Crazy person. Whichever politically correct moniker you prefer. You're looking for articles, blogs, race reports, collecting ever scrap of advice that could possibly help you. And you're starting to feel a little bit overwhelmed.
I had the same problem, and I'm realizing that I've passed on the same thing to the beginners I coach in my club. It's difficult to separate out what resources are beneficial for the beginner, what workouts will be helpful for them, what to tell them without completely freaking them out.
What I'm discovering (I think) is that it's vitally important to find a single thing on which to focus. This holds true for more experienced athletes, as well; for example, my single biggest goal for this year is to place in my age group at Shawnee Mission. That is the primary driving force behind my training. Notice I said "primary"; it's not like I'm working harder in every tough workout by chanting "Shawnee Mission Shawnee Mission Shawnee Mission." I'm also focused on building mental toughness, harnessing more discipline, building a stronger aerobic base; I have a handful of goals that are jostling in the back of my head during every workout.
I propose that the difference between the first-timer and the experienced triathlete--even a newly-minted, fresh-from-the-first-race green horn--is that the athlete with experience knows what they want and need. Athletes fresh from their first race will know exactly what I'm talking about. As you're running the last miles of your race, or right after you cross the finish line, you think, "This is what I want to do differently next time."
That next time is your focus. Until you've got that focus, all of your internet trolling, your message board questions, your desperate search through the library to find a triathlon book that was published more recently than 1998 is nothing more than guesswork. You might know roughly what you need to do (i.e. learn to swim), but as far as the kind of nuanced training suggestions you get from training guides (i.e. setting up complicated schedules based on percentages of time spent in each of five training zones) will be pretty useless to you.
With that in mind, I'd like to suggest the following focal point for the n00b: get through that first race. I absolutely guarantee that after that first race you'll have a much better sense of what you need to do. After that first race you can work on taking flying leaps onto your bike, setting up your transition area just so, shaving off seconds on the bike with advanced aerodynamic techniques (not to mention shaving your legs, men), and finding the perfect suit to wear.
Also keep in mind that even the first Ironman athletes were pretty dorky (see some of the early Kona experiences in Becoming an Ironman for a perfect example). None of us are going to laugh at you if you're wearing basketball shorts, your race shirt, and your son's bike helmet; I've been passed by people dressed exactly thus while riding a beat-up mountain bike--believe me, there was no laughing when they pushed past me up the hills at Pumpkinman a couple years ago.
My point is that you just need to get a race under your belt, then take it from there. Then after you've done that first race, post a race report somewhere online; not only will you probably get helpful responses from fellow athletes (and a big welcome to the community), you'll also have a better sense from writing out your experience what you want to do next time.
Triathlon is a sport that rewards attention to detail and dropping big bucks on equipment, but almost all of us did it the hard way first. If you read Becoming an Ironman (which I highly recommend), you realize that everyone--even the most elite competitors--started at square one, not knowing this sport or how to handle it. And there's something beautifully poignant about that initial confusion, the first few tentative steps into what is a very complex and intimidating world. Think of it as a coming-of-age.
And as rites of passage go, it sure beats a bris.