Updating taxes for all products

I'm trying to figure out the tax situation and according to the how-to all products that will have the possibility of tax must have the tax class setting changed to that tax in their product data. I have ~18000 products so it would be a pretty miserable time updating all of them manually. Is there a way to set it all automatically? It's the only tax/geo zone I have and they all need to be changed to it.

Thanks

I'm digging through the database and see that I just want the tax_class_id value to be set to 10 from the 0 it's at now in the product table. Could I just go through and change all those and have it fixed or would that affect it in a different way?

I'm pretty sure that will work. You could run this SQL so you don't have to do it manually:

update product
set tax_class_id = 10
where tax_class_id = 0

Back up first just in case.