The only options in Elements are Kodak and Shutterfly, geared mainly to the US market. I think books are so personal and you need to test one or two companies to ensure you are happy with the print quality and binding.
Personally I prepare the images in Elements (sRGB at 300 ppi and the appropriate size) then upload using the downloaded software and built-in templates.
I’ve tried a few firms in the UK and settled on the one I like. I’ve kept their software and uninstalled the other programs.
The good thing is that they send me discount coupons from time to time so I always have a set of images pre-prepared to take advantage of the offers.