I found and downloaded the free "beamsonic" impulses pack, and he includes a number of impulses of studio gear that he had, including tubes, preamps, and compressors. How do you use these impulses? For example, if it is of a compressor, do you put the compression plugin before or after the impulse in the effect chain?

Only dynamic convolution can simulate compressors and tube amps. Otherwise, the impulse is only of one amplitude level of the device, which is not a simulation of saturation or dynamic gain, only frequency response at that amplitude.

Because it is only the frequency response, the impulse is not accurately simulating the device. Some of the filtering might have happened before or after the compression or amplification.

So just try the impulses before and/or after the compression or tube amp sim.

Voxengo released Analog flux suite which has a simple but very efficient impulse response file loader in the pack as well as a tape bus built upon impulse files.
The IR vst comes with a selection of built in compressor and preamp I r's. After Ive built an fx chain I simply pop this on at the end with a file of whatever. You have to take into account the latency though. There are also many freeware alternatives to try..