Distro: Slackware 12.0
Box: HP tx 1220us
Error Message:
3ddesk
Attempting to start 3ddesktop server.
3ddeskd: error while loading shared libraries: libImlib2.so.1: cannot open shared object file: No such file or directory
Server not found after waiting 5 seconds.
Could not find server.
Try starting manually (3ddeskd)

I gather from the error message that 3D Desktop is looking in the wrong place for Imlib2. This makes sense, because I am stupid and don't know the basics of installing things :-(. I extracted the Imlib2 folder onto my desktop and installed it from there. Then I ran the 3D Desktop installer and said that the Imlib2-config file was not in my $PATH. So I moved a copy of the config and ran the installer and it worked just fine. But now when I run 3D Desktop I get the error I listed above.

This should be an easy fix, but this is the first time that I have run Linux and I do not know enough :-(. Any help would be appreciated!

Also, what should I do to avoid this is in the future? I guess I do not really know where to put things when I install them. Where should the 3D Desktop folder go, for instance?

When you execute ~$whereis libImlib2.so.1, where does the shared library show up, or does it show up at all? If it does not show up, a quick look through /lib, /usr/lib, and /usr/local/lib would be good places to start. When you find it, is the path where the file is located in /etc/ld.so.conf?

This is what shows up:
whereis libImlib2.so.1
libImlib2.so:

That doesn't look like a path; I don't really know what that means. Also, I had a look through the folders you suggested and came up with nothing. Should I try extracting the library again but place it in one of those directories?

EDIT: So reinstalled and here is what I got...

~$3ddesk
Attempting to start 3ddesktop server.
3ddeskd: error while loading shared libraries: libImlib2.so.1: cannot open shared object file: No such file or directory
Server not found after waiting 5 seconds.
Could not find server.
Try starting manually (3ddeskd)

~$whereis libImlib2.so.1
libImlib2.so: /usr/local/lib/libImlib2.so.1 /usr/local/lib/libImlib2.so

So why can't it find the file?
Here is my ld.so.conf file....

/usr/local/lib
/usr/i486-slackware-linux/lib
/usr/lib/qt/lib
/usr/lib/seamonkey

It seems to be in the correct path.

When you say reinstalled, do you mean you reinstalled 3ddesk or the imlib? Based on above, executing "ldconfig" as root should solve your problem