Spot Pantone to CMYK processed with ease?

Hi,

I am placing a series of graphic art samples that consist of Pantone spot colors into what will be a CMYK (processed color) document for a presentation.
How can I convert all the samples that are Pantone assigned color to CMYK easily?? Is there a broad selection sort of solution because these are detailed & I don't want to have to individually click each & every element by hand + click on the color mixer to convert...that would take ages!
Surely you've got the answer? -- Thanks!