Well, at least on my laptop...
$ sysctl hw.acpi.thermal.
will yield sysctl based data on my systems tempature, according to the hw.acpi.thermal.tz0.temperature sysctl is probably what you want, but refer to
acpi_thermal(4) for details on them. The childern of dev.cpu.
N will probably tell you what you want about the CPU, replace 'N' with the CPUs number, if you have one single core CPU, this is dev.cpu.0. You should be able to find the current (approximate, not exact) clock frequency of your cpu in Mhz through dev.cpu.
N.freq, but refer to [fman=4]cpufreq[/url] for details.
$ sysctl hw.acpi.thermal. dev.cpu. | $PAGER
will probably tell you plenty.