css help please

hello all…i hope i’m in the right place.
i use dreamweaver often and have a working knowledge of css (not expert but not newbie either) but am having a time trying to
change things like fonts. i’d like to use Monotype Corsiva
in the heading while the body remains in its default font.this font is not available as a option.
i’m running wp 3.1 with thesis 1.8.
i would also like to right align a small 170×170 logo image centered in the header div. in dw this is simple as i create my own layouts but seeing as so much has already been created behind the scenes with wp & thesis i am at a loss. for instance, i usually create a header in dw 948×109 but how can i find the measurements of the header div in wp or thesis?
i thank all who may assist me…Thank you.