I'm doing the London 10k run in July as a fundraiser for The Bike Experience.
Starting this weekend, I'm going to be doing the Swindon 5k each week as well as my normal training. For those looking at the Royal Marines Race, it may also be useful. One of the guys at my gym recommended it to me. You just enter, and they send you a barcode by email that you take along, and hand in at the end to get your times.
Register online at http://www.parkrun.org.uk/swindon/home and let me know if you're planning on coming along as it would be nice to have someone else there that I know!
I can currently do 5k in 36mins on the treadmill, so hoping I can get that down to 25 mins over the next couple of months. I've been advised that, although road running is physically more demanding, because of the scenery changes, and the fact you run in groups, it's often easier to go quicker and more enjoyable. I hope that's true!