>> I have some problem setting up my deskjet 500 on my NetBSD system(1.0 on Amiga).
>>
>> a) i set up the printcap to use the /dev/lp .But if i send a file (text file)
>>   to it, only the first line is printed (cat myfile >/dev/lp)

>> b) Is ther any postscript driver for the Deskjet 500 that i canu use? i have Xfig

Yes, there is ghoscript which can convert postscript to PCL code.

I use the following line...
gs -dSAFER -dNOPAUSE -q -sOutputFile=- -sPAPERSIZE=a4 -sDEVICE=cdj550 < my_file.ps > my_file.pcl

You sould try djet500 instead of cdj550, and compile gs with the required driver.

You could add if=ps_to_pcl in the /etc/printcap and create a script 'ps_to_pcl'
executing the previous command.