If you can afford to throw a big chunk of time at it and you want to have a dabble, then for around £150'ish you can put together a DIY kit that will help you get started. There are three bits you need plus a laptop: You want some decent test discs to give you accurate source images. A light sensor to pick up the output from the display, and a PC program to interpret the readings.
Pro's like me won't use this level of gear. It's not fast enough or accurate enough. But for a home user it'll help you make a big difference in performance compared to just setting up with THX Optimode (Free, but limited and not that accurate) or Digital Video Essentials which is actually a very useful tool for less than £15.
If you want to get serious then the cost of the gear and software goes up quite a step. My stuff is £2000. The next level up you're looking at £7K+
Having the right gear though is only half the story. You need to know what you're doing with it. That kind of knowledge only comes with time and experience. It's not too hard to learn if you're just doing your own TV, but don't expect to get it right the first couple of times you try. Set aside 30-40 hours research and tinkering time. I'll also give you fair warning now - quite a few TVs require that you access the service menu to do a calibration. There are settings in there that can kill a TV. Proceed with caution.
DIY vs getting a Pro in: DIY is great fun. If you have the money and time to spare then I'd recommend having a go. You'll learn a lot about the way displays work and be a far better judge of quality as a result.
Getting a Pro in will give superior results in a fraction of the time. I generally set aside a morning or afternoon to calibrate a display for the main sources it will see.
Most of my fellow calibrators charge £250-£400 depending on the depth they go to. It's a chunk of money, but when you compare the result next to what you'd have to spend in a hardware upgrade to get a similar benefit then it all makes perfect sense. When a £700 projector can be calibrated and then go on to beat a model at twice the price then you have to conclude that it's £300 well spent.
