Hi,
There are a lot of excellent free wordpress theme available in wordpress.org. Also a number of premium theme providers sometime distribute free themes. Based on the subject you want to display in your site, I can refer a free one for your use.
Hosting starts the moment you pay the provider and within 5 minutes of paying for the space you can start using it. However, DNS propagation (linking your domain /site name to the hosting space) may take upto 48 hours. I hope that within that 48 hours, you will be able to put your content in the site and it will be ready for public viewing.
For any further explanation, you may contact me.