when trying to compile pygtk I get the following error:

[QUOTE]/bin/sed: can't read /usr/lib/libcairo.la: No such file or directory
libtool: link: `/usr/lib/libcairo.la' is not a valid libtool archive{/QUOTE]

libcairo.la is in /usr/local/lib/, so what do I pass to tell it this?

well it's just kind of strange that libcairo.la is in /usr/local
which is the place for experimental not system libs.
it's been a long time since i built gnome and freinds but by putting some of it in /usr/local i think you are making a mess.
yes i can think of hack ways to recover but better rethink what you are doing before the mess gets worse.

I didn't specify to put it there, it just installed it there by default for some reason

yea the default ./configure never overwrites system files but rather they go in /usr/local for safety
when you are actually installing something to your system you put it with ./configure --prefix=/usr

BUT do you have another system libciaro in /usr that goes with your gtk ?
this is what i have seen people do so often

if you are going to install upgraded versions of gtk/gnome junk i think uninstall the other stuff first or use your systems package manager.

running two versions of modern gtk is not for the uninitiated.
it's not imposible because obviously the developers do it. it's just a huge mess unless you know what you are doing.

no, I do not have another version of libcairo there, that's why I don't understand why it did this from what you are telling me.

edit: I did have another version of cairo installed which I was sure to uninstall with slackwares package manager beforehand I think.

yea it could be alot of reasons. (i don't mean to come off like lecturer)
basically the configure script is making a guess or an informed guess because your gtk is in /usr.
it might work to have it in /usr/local with some fudging but to be on the safe side i would reinstall cairo with
./configure --prefix=/usr
you can't really be sure your gtk will still work because it was linked against the old cairo
but it very well might be just fine.