My local running store is offering a 12-week 10-K prep program (before a local 10K that I can't run because of work/travel plans).
Should I sign up? It's 2 runs/week, plus some seminars etc, for $100. I will miss 3 weeks' worth because of work and family travel, including the first week (info session and one run) and the last 2 weeks (including the 10K race.)
The thing is, I can already run 10K. And I know what I need to do to get faster/better. But it might be fun to run with other people (I've never tried) and it might motivate me/help me run at different times.
I did a half marathon training program last summer prior to HM #7. I had long run company, made some new friends, and ran a PR, so I'd say it was worth it.