Parallel to USB for my printer (HP DeskJet)

Just google around, you may find some products. There is one availabe from Belkin.

I am not sure but it seems that we are talking about a cable with a USB on one and a parallel port in the other end; with other words I guess that it is the same as USB->parallel (sorry, but I cannot guarantee that!).

You should consider that the adapter has to be compatible to MacOS X. Most of them offered in Web are stated as compatible to Windows only, but as I stated above there is one for Mac provided by Belkin:

A review:
http://www.macease.com/review-parallelto_usbada.html

The product:
http://catalog.belkin.com/IWCatProductPage.process?MerchantId=&ProductId=20651#

"USB to Parallel" and "Parallel to USB" are the same thing. The USB end of these cables must always plug into a computer, and the parallel end of these cables must always plug into the peripheral device.

What model of Deskjet printer are you trying to use? Is it essential that you use this particular printer? Given the low cost of new inkjet printers, the cost of a USB-to-parallel adapter cable, and the fact that a brand new printer will likely outperform your old Deskjet printer in every possible way - it makes little sense trying to adapt an old printer for use with a Mac.

Trying to use a switch for a pc andImac g3 so that I can use Deskjet for both computes - where does one get the usb/parallel adapter for mac - I have the one for PC