Hi Emmy
Since 8.5x11" is not a "standard" industry size...you would have to place your LO on the next largest size canvas (that is standard) and pay that price and ask that they trim it for you. For example...when I have 6x6 pages printed for gift albums...6x6 is not a standard size...so I place four 6x6 LO's on a 12x12 canvas and then cut them...hope that helps...
and for pricing info on the site....click on services...then click on "thrifty digital output" (or any other category you might wish to use)...then pricing should be listed on that page for the respective sizes! Good luck!
Kristie