Flat tyres are fun...I know others have found the process relatively simple, but I (and a few bike mechanics) had a lot of "fun" with getting my flat tyre changed and back on the rim over the weekend.
Luckily it was the rear, so I was able to get the wheel off fairly simply and after a few hours of swearing and cursing, took it to a local bike shop and they eventually levered the tyre back onto the rim and inflated the tyre for me...and I am back on the road.
Keep the pressure up in those tyres, people. My puncture was a pinch-flat due to the pressure being too low and a commination of my weight and the terrain pinching the sidewall and popping the inner-tube.
I'm now running at a shade over 50psi and will be putting slime in my tyres as soon as it arrives...