I think from IBM's point of view they probably will only support the laptop in the state it was when you took it out of it's box. Since Linux wasn't part of the package deal I think you'll find that you're working outside of warranty (in case it would be under warranty. if it isn't, then that statement goes out the window(s) )
And as far as IBM's Linux support goes.. perhaps that's only for their server based solutions, but I could be mistaking about that ofcourse.
If you want technical support for Linux, you're probably better off contacting the makers of your distribution. E.g. if you got Mandrake, go to Mandrake. SuSe? go to SuSe. Etc.
Or, hang around here and ask around for solutions to your Linux problems