I'm not an expert but I have recorded a fair bit of piano in the past ( Mostly uprights). How you record it will depend on what your recording. Classical piano, and pop piano are two totally different sounds.
I've tried lots of different types of mics, but what I found worked best were a pair of pencil condensor mics, with a cardiod pattern. I found omni's just added to much air, and lost some sonic qualities of the pianos, and you definetly won't want that if its a pop sound your after.
Most books will tell you to place the mics above the hammers. That works, but personnally I found that if I put them father down the soundboard the sound wasn't quite as percussive, and I got more tone from the piano. You will also pick up some of the harmonics from the piano, rather than just the fundamental tone where the hammers hit the strings.
When you mix it, run it through a multiband compressor, ( the waves Linear MB will work real well) and then you can clean up any voicing problems with the piano. But of course before you start make the sure piano is tuned, and that the regualtion and voicing of the piano are okay. No matter what equipment you have, and how you record it, it will sound like crap if the piano's not in good shape. So make sure you get a good technician.
Let us know how it goes!