Help: After install glib-2.0.6, can't find glib.h. (but it's there!)

[Karl and Tanya Pizzolatto <karlandtanya earthlink net>]

I'm trying to install the latest gtk+ in order to compile and use MJpegTools 
& some other stuff.

I'm having some trouble.  I think my problem is libraries (include files?), 
or whatever tells the system where they are.    I started my process by 
building and installing glib-2.0.6.  Next, I tried to configure some 
packages that depend on it (atk-1.0.3, pango-1.0.4) and they don't seem to 
be able to find the libraries. 

The error message is "checking for GLIB - version >=2.0.0...no

What do I need to do to tell (whoever needs to know) where this library is?
Do I need to specify something when I ./configure make make install glib?

Here's what I did:
download glib-2.0.6, gtk+-2.0.6, pango-1.0.4, pango-fonts-0.3, and 
atk-1.0.3.  All from www.gtk.org.

Next, I used removekpg to get rid of gtk-1.whatever comes with Slackware 
8.1. ('Cause I'm about to install a later version).

Then untar glib-2.0.g.tar.gz, and ./configure, make, su, make install.

Everything seems to go fine; no error messages.  Default prefix is 
/usr/local.

Then I said ldconfig (as user and as root--tried it twice). 

Ok, now I try to make one of the packages that needs glib:
tar zxpvf atk-1.0.3.tar.gz, ./configure
And the error message from ./configure:
"checking for GLIB - version >=2.0.0...no"

Note that glib.h does exist, and it's in: /usr/local/include/glib-2.0/glib.h

and looking at config.log, I see several errors.  This appears to be the 
relevant one:

...
configure:7235: checking for pkg-config
configure:7253: found /usr/bin/pkg-config
configure:7266: result: /usr/bin/pkg-config
configure:7289: checking for GLIB - version >= 2.0.0
configure:7434: result: no
configure:7470: gcc -o conftest -g -O2 -Wall    conftest.c   >&5
configure:7450: glib.h: No such file or directory
configure:7473: $? = 1
configure: failed program was:
#line 7448 "configure"
#include "confdefs.h"

#include <glib.h>
#include <stdio.h>

#ifdef F77_DUMMY_MAIN
#  ifdef __cplusplus
     extern "C"
#  endif
   int F77_DUMMY_MAIN() { return 1; }
#endif
int
main ()
{
 return ((glib_major_version) || (glib_minor_version) || 
(glib_micro_version));
  ;
  return 0;
}
configure:7508: error:
*** GLIB 2.0.0 or better is required. The latest version of
*** GLIB is always available from ftp://ftp.gtk.org/.
...

Help--what do I do?

Somebody smarter than me, please post an answer here!

Thanks

Karl Pizzolatto
freedom isn't free
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