Oh, I'm running on a macbook as well! We must have different models though, because I have a function key - not that I ever need to use fn for DF. Honestly, you can get by using shift+* & shift+/ for scrolling up/down, shift+< and shift +> for scrolling z axis, etc. diagonal movement is totally covered by your regular number keys -
1 3
7 9
for the different directions.
Also the lazy newb pack just combines a lot of pretty okay extras for DF, like some popular chipsets and keybindings that are sensible for a laptop without a numpad. I've never used it though, so I'm unsure of whether or not it relies on a function key.
I've been playing with a laptop for a couple of months now. It's really not a big deal :V the only thing I haven't yet figured out is how to scroll down the list of items you're (L)ooking at in adventure mode.
You scroll it with * and /, not only the numpad version of those keys work, but the normal ones will do too (i don't know where they are on an English keyboard tho, mine are shift-7 and shift-+)
But if you use that without a numpad, it will also think you're pressing "shift+8" and move like ten squares north. The closest thing I can find to a solution it to press "Shift+8+down/2" to try to cancel out the movement which rapidly switches your screen between two spots and if you're lucky will leave it scrolled down on the inventory screen when you stop.
Oh! I guess it doesn't really matter so much, haha. I usually just walk up and hit (G)et and cycle through that menu.