If you like Thompson's writing or ideas, or would like to observe more of the "gonzo" character, then in addition to the writings check out a 1978 BBC mini-documentary "Fear and loathing in gonzo-vision". A journalist and cameraperson go around with HST for a few days, there are casual interviews, some on-the-scene scenes and some background. Vids with that or similar names may be on youtube (I can't verify right now); also discs and torrents.