I myself have turned down many requests to be event photographer because I have only shot photos for my own pleasure and cannot guarantee anything. Plus, I shoot with 35mm which means it's even more unforgiving if the light condition isn't favorable. I'd say if you want to become an event photographer, start with doing it for free, or as the second/back-up photographer. Communication with your client is also very important. You NEED to deliver up to, or surpass their expectations. An event like wedding is one of the hardest. I'd suggest really know the schedule inside out, when things are expected to happen and plan for them. Also, know the venue inside out too. You need to be at the right place at the right time. Knowing the weather is another thing. If it's going to be cloudy, then have a strategy to make the best use of it.
Equipment for wedding event is also very demanding. Good lens for indoor shots. Portrait and wide angle to telephoto, you almost need everything, not to mention a good mobile flash set up and the skill to use them properly. You need a lot of experience for sure. That's why people spend 4 years in photography schools.
Here's a really good example of someone who started out as a recreational photographer and became a pro:
* ±B§¬ö¿ý½g* Photo Gallery by Albert Jou at pbase.com
The message below actually says he's sorry that he cannot take any more reservations because he's completely booked for the rest of the year.
With regards to monitor calibration, this is very important for ANY profession that deals with image output. Photographers, graphic designers, publishers etc. Basically, you need to calibrate all of your imaging devices, from scanners, monitors to printers. Design consultancies will hire professionals to calibrate EVERY scanner, monitor and printer that they own. It's useless to create an image that looks to be beautiful on your own screen and turn out to be off when printed on the final medium. My laptop has really inaccurate color saturation which is beyond adjustment, so I use a separate monitor that is closer to my printer whenever I need to process any image. Also, when making a print from a commercial printer, always proof read them before them make the actual print. This isn't about making sure that there's no spelling error, but making sure if the image comes out right. Otherwise, you will be wasting both time and money.
So, going pro is not just about being able to click your camera trigger. You need to be able to provide the whole package, from the beginning to the final output. Whether you outsource part of your service or not, you need to have a network of resources to back you up. If you cannot make prints yourself, then establish a good relationship with a trust worthy commercial printer to do the work for you. Rule of thumb is, everything that goes out to your clients represents your reputation. Everything you send out should go through your hands before they are delivered.