Specifications, manuals and manufacturer support often are not helpful. Therefore you should retrieve information from other sources too:
TuxMobil Linux Laptop and Notebook Survey , this survey covers other UniXes (for example BSD, Solaris), too.
General information about manufacturer support you may find in my Linux Status Survey of Laptop and Notebook Manufacturers , though don't expect to much Linux support from them yet. Sometimes the Matrix of OEM/ODM Relations may help to find information for your laptop under another brand name.