you could go oldschool… check the newspaper classifieds, or put out an ad yourself, advertising that you’re available to play such gigs… obviously that would require a capital investment on your part.
a lot of the music business is networking… it’s all about who you know, ya know? haha. so much is communicated by word-of-mouth. if you’re in a big city, and you’re really a legit excellent pianist and can read music well, you could apply at a recording studio to be a studio musician (basically being a utility player for bands that wanna record something with a piano part, that don’t have a pianist). those gigs are pretty tough to get though, but they pay decent, that’s for sure.

if you live in london go to a website called gumtree.com and post as ad

if you live in any different country go to the same websie and change the place and if will give u a smillr website…

try it dude