Site got virus, where are product files?

Hi all,

I use WP all i one security plugin but still my site got infected by payday loans virus.
I have hundreds pages offering loans that are not visible in Pages menu.
How do I get my site cleared from this spam?
I have over 2’600 products and do not want to lose my content.
Categories and products are my main concern and was hoping I can start from the scratches by exporting categories & products and then importing back to clear install.
Any help will be appreciate!