If I had known this tidbit, I wouldn't have bought the printer...
The HP LaserJet 1000 has no persistent firmware (can you even use the term 'firmware'?); the Windows driver sends the firmware on startup to the printer. It was a way to keep the cost of the printer down below US$200 (I paid $199 at CompUSA). A rather STUPID way to reduce cost, but since most prnters are used in a Windows environment anyway, it seems that HP decided it wouldn't be a problem.
Anyway, over at linuxprinting.org, there is a write-up on getting the LJ1000 to work plus more details on the printer itself...
Part of the writeup is about sending the firmware via the cat command as root. After downloading the updated software from HP, extract the firmware from the self-extracting exe file (don't use the one on the CD I am told) and send it to the printer:
# cat sihp1000.img > /dev/usb/lp0
This uploads the firmware to the printer. Do this ONCE and ONCE ONLY; do it twice, and you will have to power cycle the printer and send it again.
I personally am yet to get it to work, but I haven't done everything suggested in the linuxprinting write-up.