Excellent thread, with multiple thoughtful replies (and points of view). Thanks for starting it!
OP, your posts indicate that you have a good grasp of the situation, and multiple responses have suggested the "grind it out" route that you may have to take in order to be a college coach--which I think is ultimately possible for you. You have several assets:
*Successful competitive experience
(If you were a "name" athlete--Olympic team level, or something close--that by itself might open doors, but it doesn't seem like you were.)
*Certified Strength and Conditioning Specialist (CSCS)
(This is an excellent and well-respected "cert"--one that not a lot of LRCers may know about--and you definitely should highlight it on your resume and in your conversations with potential employers.)
*Continuing participation in the sport
(But be very careful here. You must make it clear that your own running is not a priority, just a way for you to stay fit and relate to your athletes.)
*Experience in office work and record keeping
(Again, valuable qualities in an assistant coach, and if you have a reference who'd vouch for this experience it'll help you.)
*A burning, long-lasting desire to coach
(This is key, and will sustain you through the years while you're building a career and living with the "vows"--of poverty, chastity, and obedience--that are the assistant's lot.)
You have a lot going for you and I believe you can succeed. It probably won't be easy--but you already seem to know that.
Others have already given helpful tips: about expanding your event coverage and going the grad-assistant route, for instance. I also always advise undergrads who think they'd like to coach to take a computer major or minor, if they can handle it; you're out of college, but if there's any kind of credible computer credential you can get, I'd say do so. Athletic depts *love* having a "geek" on staff.
Beyond that: assuming USATF still has a certification program for coaches, get involved with that immediately and work to at least Level Two--in event areas *other* than distance running--just as soon as possible. (Similarly, work on other events yourself. You'll learn *tons*. I personally recommend discus--an event that just feels good--but you really need to give a lot of things a decent try, if you can do it without crippling yourself!)
At those clinics--Do they still do them as clinics, or strictly online?--meet working coaches (high school and club, as well as college) who are attending, and get to know them. Take your resume and ask them to critique it; make clear that you're *not* asking them for a job, but that you want to know what they're looking for in a resume. A (potential) coach's resume is NOT going to be structured like the resume your college placement office recommended.
The main thing, really--as others have said--is that you're going to have to get to know coaches. If you're not a natural hail-fellow-well-met kind of guy, that's not necessarily a problem--don't try to be a personality that you're not, because people can spot phonies--but if you're pretty shy and not comfortable starting a conversation, you need to change some--or, if you *did* find a job, you wouldn't be successful as a recruiter, which is KEY to a college coaching career.
Let me repeat that. You will need to develop an enjoyment of the entire recruiting process. Your office experience/habits will help with the identify/contact phases, but you'll need to cultivate the (real) pleasures of getting to meet prospective students and their families, traveling to meets and prospects' homes, keeping in touch with phone calls and correspondence, etc.
Good luck to you!