You only need around $15 or so to start your first WP blog. .info domains are cheap for the first year, and you can get hosting for as less as $1/mo from some of the providers in the web hosting section here.
You don't need paid hosting, You can run your blog on a good free hosting service like frihost.com When you yr blog grows and also when you start earn from it you can move to paid host if it needs an one.