When providing logos for your artwork, it is preferable to recieve a eps file that has been designed within a vector based software. Even with a large font database, it may still be necessary for you to provide a font, however logo re-designs can be done.
Using vector images for your logo and also for any illustrations gives a much clearer and defined line that using any pixel based imagery (as in Photographs). Click below to see the difference, using the same image, but saved vector vs pixel.
You should supply high resolution photographs that should not be less than 300dpi at the actual size you wish the photograph to appear in your artwork. EG, a file at 10cm x 10cm at 150dpi will look best at 5cm x 5cm or else pixellated.
Artwork that requires specific Pantone colours, eg, for a logo, or any metallic or spot gloss coating, etc, will need to be printed via Lithographic print machines. These require printing plates, run through machines in 4 or more stages.