check out the contents of /proc/acpi for info
for example, to find the temperature of your box you would type 'cat /proc/acpi/thermal_zone/THRM/temperature'
so on and so forth...for trip points, replace the relvant lines, etc etc..
EDIT: You should also check this http://ibm-acpi.sourceforge.net/
out..it says it supports additional acpi functions that the generic ones dont, sounds right for you but ymmv, as i have noexperience with it or if its depracated or not.
but to give you an idea of what you need to be googling for (and how i found that site)...the terms i used were 'ibm thinkpad acpi fan linux'
okay good luck