Got a fresh copy of Xp installed, have all my stuff for slackware 11, but im having problems figuring out how to install the damn thing. never had a problem with redhat, debian or fedora core, but i don't exactly get how to do it.

Ok, i dont know exactly what your questions really is, or where you are having problems,but I will give some general dual booting with windows advice.
1st install windows before any linux distro.
2nd Install linux second, and maybe use extended partition with logical partitions following it instead of primary partitions (after the windows one)
3rd Install Grub or Lilo, from what i have seen most distros will automatically install one of the two with the linux install, that will also detect your windows.

I get what oyu mean, im just having problems now trying to partition the damn thing.

And the way the setup is made for Slackware when you first boot up, its a bit confusing to figure out what your doing.

Well the best way to go about it is to boot up a Live CD and use the terminal program cfdisk to create

(1) hda1 (or sda1 for Sata) for XP, make the partition type 7 for ntfs filing system.

(2) hda2 and hda3 for Slackware. Partitions created by Linux automatically Type 83 suitable for any Linux installation but you need to make one of the two Type 82 for swap. For example say hda3 is swap.

When you install XP it will know where to go immediately.

When you install Slackware just tell the installer to install Linux in hda2 and everything will fall into place.

Lilo is the standard boot loader in Slackware. It should dual boot XP automatically after the installation. If it doesn´t edit /etc/lilo.conf to make sure it has the following lines inside

Exactly which part of the installation are you having problems with?