Grips? See Hakan - great stuff in wood, or rubber from CZ. I am still fine with my plastic factory ones until I can get my Hakans.
CZ carries the PT night sights, but I have heard both good and bad about them, and about thier competitor, Meprolight. I think Kev(CZ75ID) has a set of PT's on his.
Hi cap Compact mags are scarce as hens teeth. The full size hicap(15 rnd) will work fine, but stick out of the bottom a little. In 2004 the magazine ban sunsets, and the good Lord willin', an' the crik don' rise, we can start getting hi caps agin.
Some holsters for the Glock 19 fit pretty well, but check out the stuff from High Noon; thier link is in the Pistols section. Nice looking rigs at a decent price.
Welcome to the CZ75 Compact Club!
Dave